Publications

• Ratz, Andrew W.; Arnold, A. Elizabeth; Burrill, Haley M.; Caiafa, Marcos V.; Conery, John & Dawson, Heather A. [Show all 19 contributors for this article] (2026). Sporecasting Biogeography Across Scales: Continental Patterns and Local Constraints on Macrofungal Dispersal. Molecular Ecology. ISSN 0962-1083. 35(9), p. 1–17. doi: 10.1111/mec.70366. Full text in Research Archive
• Danieli, Krubeal & Lepperød, Mikkel Elle (2026). Flexible navigation with neuromodulated cognitive maps. PLoS Computational Biology. ISSN 1553-734X. 22(7), p. 1013487–1013487. doi: 10.1371/journal.pcbi.1013487. Full text in Research Archive Show summary

  Animals develop specialized cognitive maps during navigation, constructing environmental representations that facilitate efficient exploration and goal-directed planning. The hippocampal CA1 region is implicated as the primary neural substrate for cognitive mapping, housing spatially tuned cells that adapt based on behavioral patterns and internal states. Computational approaches to modeling these biological systems have employed various methodologies. Although labeled graphs with local spatial information and deep neural networks have provided computational frameworks for spatial navigation, significant limitations persist in modeling one-shot adaptive mapping. We introduce a biologically inspired place cell architecture that develops cognitive maps during exploration of novel environments. Our model implements a simulated agent for reward-driven navigation that forms spatial representations online. The architecture incorporates behaviorally relevant information through neuromodulatory signals that respond to environmental boundaries and reward locations. Learning combines rapid Hebbian plasticity, lateral competition, and targeted modulation of place cells. Analysis of the model across a variety of environments demonstrates that online map formation and reward-directed navigation can emerge within a single simulated trial, without the multi-epoch training typically required by reinforcement-learning approaches. The simulation results show that the agent successfully explores and navigates to target locations in various environments, adapting when reward positions change. Analysis of neuromodulated place cells reveals dynamic changes in neuronal density and place field size after behaviorally significant events. These findings align with experimental observations of reward effects on hippocampal spatial cells while providing computational support for the efficacy of biologically inspired approaches to cognitive mapping.

• Maurstad, Marius Filomeno; Kusy, Dominik; Undheim, Eivind Andreas Baste; Jakobsen, Kjetill Sigurd; Böhne, Astrid & Monteiro, Rita [Show all 20 contributors for this article] (2026). ERGA-BGE chromosome-level genome assembly of the giant stream lacewing  Osmylus fulvicephalus (Scopoli, 1763). Open Research Europe. 6. doi: 10.12688/openreseurope.23457.3. Full text in Research Archive Show summary

  The giant stream lacewing, Osmylus fulvicephalus (Scopoli, 1763), is a widespread European species belonging to the insect order Neuroptera. Its cryptic larvae are predators found at the banks of streams and smaller rivers where they use their piercing, lance-shaped stylets to inject venom into their arthropod prey. Here, we present the reference genome of the giant stream lacewing as a crucial resource for uncovering the genetic basis of venom evolution in Neuroptera. The chromosome-level genome encompasses 674.7 Mb and is composed of 60 contigs and 24 scaffolds where 99.2% of the assembly is distributed among the 6 contiguous chromosomal pseudomolecules and two sex chromosomes (X and Y). Contig and scaffold N50 have a value of 51.5 Mb and 116.2 Mb, respectively. This reference genome is the first genomic resource from the family of lance lacewings, providing valuable data for clarifying the phylogenetic placement of the family Osmylidae within Neuroptera.

• Essner, Rachel A.; Ruda, Kiersten; Choh, Hannah J.; Kucukdereli, Hakan; Amsalem, Oren & Edelhaus, Julia [Show all 11 contributors for this article] (2026). Brainstem sensing of multiple body signals during food consumption. Neuron. ISSN 0896-6273. doi: 10.1016/j.neuron.2026.08.015. Full text in Research Archive
• Vu, Trong Dai; Le, Minh Hoang & Dinh, van Khuong (2026). Extreme warming increases metabolic demand and diminishes acidification effects on larval survival in the dog conch Strombus canarium. Frontiers in Marine Science. 13, p. 1–11. doi: 10.3389/fmars.2026.1914485. Full text in Research Archive
• Munoz, Sara Orellana; Haberkorn, Chloé; Csoboz, Balint; Stelkens, Rike & Peris, David (2026). Mitochondrial inheritance as an important parameter for the rational design of synthetic yeast polyploids. BioRxiv. ISSN 0362-4331. doi: https:/www.biorxiv.org/content/10.64898/2026.09.22.753424v1. Full text in Research Archive
• Lettenmaier, Ludwig; Eisenhauer, Nico; Cesarz, Simone; Ammer, Christian; Bucharova, Anna & Dittrich, Sebastian [Show all 16 contributors for this article] (2026). Native earthworms and roe deer in temperate forests: Friends in the sun, foes in the shade. Ecology. ISSN 0012-9658. 107(9). doi: 10.1002/ecy.70520. Full text in Research Archive
• Saragliadis, Athanasios; Hatlem, Daniel & Linke, Dirk (2026). Purification of Bacterial Lipopolysaccharide, and How to Study Its Interactions with Proteins. Methods in molecular biology. ISSN 1064-3745. 3001, p. 117–132. doi: https:/link.springer.com/protocol/10.1007/978-1-0716-5054-7_6. Full text in Research Archive
• Klemetsen, Terje; Endresen, Dag; Johnsen, Arild; Boer, Hugo de; Fossøy, Frode & Ekrem, Torbjørn [Show all 11 contributors for this article] (2026). Strengthening molecular biodiversity research and monitoring in Norway – connecting tools, data and people. F1000 Research. 15, p. (ELIXIR)–(ELIXIR). doi: 10.12688/f1000research.179210.1. Full text in Research Archive Show summary

  Background Norway’s diverse ecosystems and strong research community are well-positioned to leverage molecular approaches (DNA barcoding, eDNA, whole-genome sequencing) for biodiversity research and monitoring. However, progress is constrained by gaps in data accessibility, standardisation, and interoperability across molecular, ecological, and biobank datasets. Methods ELIXIR’s Norwegian Molecular Biodiversity Working Group mapped national actors and networks through a desk review (2024–2025) and conducted a national survey (58 questions; open from 18 February to 8 March 2024) targeting data management, standards, tooling, infrastructures, and training. The survey was implemented in Nettskjema and received 58 responses from biodiversity-related researchers. Results We identified 19 Norwegian institutes active in molecular biodiversity and 28 relevant networks, with 11 networks involving three or more institutes. The survey results highlight gaps between policy and practice: 60% of respondents were familiar with the FAIR principles, but only 29% consistently made data fully open or FAIR-compliant. Data linkage with physical specimens was often reported as missing (38% of respondents), and taxonomic assignment was frequently challenging (39.3%). Most researchers reuse published datasets (90%), but data discovery and reuse are hindered: only 41% find it easy to locate relevant data, 32% struggle to find appropriate sequence databases, 54% cite insufficient metadata, and 72% need to harmonise combined datasets. Tool discoverability and documentation were limited (32% knew bio.tools; 5% WorkflowHub; 32% agreed tools are well documented and user-friendly). Data publication is not straightforward (63.8% find it hard or answered neutral). Conclusions Norway can strengthen molecular biodiversity research by 1) connecting molecular and ecological data, collections, and biobanks using persistent identifiers; 2) adhering to international metadata standards (e.g., DwC, MIxS) and rewarding data stewardship; 3) consolidating national collaborative networks; and 4) building capacity through targeted training and dedicated data steward roles. Implementing these measures will enhance interoperability, FAIR data sharing, and Norway’s leadership in biodiversity research and conservation.

• Burton, Tim; Fiske, Peder; Forseth, Torbjørn; Hedger, Richard David; Einum, Sigurd & Falkegård, Morten [Show all 15 contributors for this article] (2026). Multi-decadal trends in abundance reveal a dramatic decline in wild Norwegian Atlantic salmon. Fisheries Research. ISSN 0165-7836. 303. doi: 10.1016/j.fishres.2026.107883. Full text in Research Archive Show summary

  Understanding changes in population abundance is critical for conservation of fish populations. Here, we esti mate abundance of wild Atlantic salmon (Salmo salar L.) in Norwegian rivers at national and regional levels using catch statistics encompassing nearly 450 populations. Estimates based on body size were reconstructed nationally (1983–2023) and for five geographic regions (1989–2023). Abundance of one-sea-winter (1SW) and multi-sea-winter (MSW) salmon was reconstructed regionally over 1989–2023. Nationwide abundance halved over four decades, consistent with declines reported elsewhere in the North Atlantic that are often linked to poorer marine growth conditions. The national decline was likely driven by pronounced reductions in the Central and South-West regions and in the River Tana, whereas abundance remained relatively stable in the Northern region and increased in the South-East region. Patterns from sea-age analyses closely mirrored those from size- based analyses. Contrasting regional abundance trajectories provided an opportunity to assess whether observed patterns were qualitatively consistent with independently documented geographic variation in anthropogenic pressures. Sensitivity analyses showed that alternative assumptions regarding unreported catch influenced the estimated magnitude of long-term abundance change but did not alter the direction of national or regional trends. Our results are consistent with reduced marine growth contributing to the nationwide decline in Atlantic salmon abundance, while the marked regional variation in abundance trajectories suggests that regionally varying anthropogenic stressors, including salmon farming, freshwater habitat degradation and human exploitation likely also contribute to finer geographic scale differences in abundance.

• Kline, Simon Hasselø; Hyvärinen, Olli Petteri; Valestrand, Louise; Andersen, Tom; Eikrem, Wenche & Titelman, Josefin [Show all 8 contributors for this article] (2026). 15-year shift in protist communities and a decline of heterotrophic dinoflagellates in the Oslofjord and Skagerrak. Frontiers in Marine Science. 13. doi: 10.3389/fmars.2026.1876109. Full text in Research Archive
• Eiler, Alexander (2026). Rethinking evolutionary inference in metagenomic time series. mSystems. 11(9). doi: 10.1128/msystems.00693-26. Full text in Research Archive Show summary

  ABSTRACT As ecologists increasingly use metagenomic time series to track evolution in the wild, there is a risk of misinterpreting ecological dynamics as rapid adaptation. This Perspective identifies methodological limitations that generate misleading signatures of microbial evolution. A primary issue is confusing evolutionary change (driven by de novo mutation or horizontal gene transfer) with ecological lineage turnover, such as seasonal oscillations or the reactivation of dormant lineages. Current metagenome-assembled genomes can collapse micro-diverse lineages and decouple adaptive mobile elements, creating inaccurate genomic signatures of sweeps or stasis. To address these issues, I propose a framework integrating long-read sequencing, pangenome graph theory, and forward-time simulations to model populations as temporal genetic networks and better resolve microbial evolutionary dynamics.

• Sanchez, Pedro Maria Martin; Wurzbacher, Christian; Fontaine, Laurent; Lara, Maria Jimenez; Juottonen, Heli & Valiente, Nicolas [Show all 9 contributors for this article] (2026). Low determinism in community assembly of transient and resident pelagic fungi across climate zones in Scandinavian lakes. mSystems. 11(9). doi: 10.1128/msystems.00691-26. Full text in Research Archive Show summary

  ABSTRACT In lakes, fungi play pivotal roles in biogeochemical processes, particularly in the decomposition of organic matter. However, these organisms have been underrepresented and taxonomically unresolved in previous research. In this study, we employ high-resolution sequencing to delve into the fungal diversity within two distinct Scandinavian Lake data sets spanning a vast latitudinal gradient across Norway and Sweden, diverse climatic zones ranging from nemoral to arctic, and a wide spectrum of nutrient conditions. Utilizing eukaryotic 18S primers, we reveal that fungi contribute, on average, 2.07% in the Norwegian and 5.4% in the Swedish sequencing data set, with remarkable spikes of up to 55% in forested lakes. Fungus-specific 5.8S-ITS2 sequencing identified the prevalence of several fungal phyla, including Ascomycota , Rozellomycota , Basidiomycota , Chytridiomycota , Aphelidiomycota , and Mortierellomycota . Notably, our research uncovers a striking degree of variability in fungal communities across the studied lakes. Null model analyses on the entire community, as well as subsets of transient and resident members, revealed that deterministic selection plays a secondary role. Instead, community assembly was overwhelmingly governed by stochastic ecological drift across all tested groups. These findings challenge conventional paradigms of eukaryotic communities being strongly guided by deterministic processes and underscore the complexity of community assembly processes across the fungal kingdom. The dominance of ecological drift and stochasticity in the assembly process emphasizes that conservation should target entire communities, processes, and areas instead of single species, as should be the case in deterministically assembled communities. IMPORTANCE Fungi perform a range of key functions in freshwater environments. Here, we show that fungi, including members of the phyla Ascomycota , Rozellomycota , Basidiomycota , and Chytridiomycota , represent a diverse part of the epilimnetic planktonic community in Scandinavian lakes. Fungal community assembly across northern climate zones is shown to have a low signal for determinism, as environmental sorting was weak in overwriting dispersal-related processes and ecological drift. Furthermore, we expand knowledge of the ecological range of key freshwater fungi and link taxa to biogeographic patterns in lakes.

• Denes, Christopher E.; D'Araujo, Tian Y.; Chung, Felicity; Lau, Man Tat; Cole, Adam & Casewell, Nicholas R. [Show all 8 contributors for this article] (2026). Sea nettle jellyfish venom targets proteoglycans to cause cell death and pain. Science Advances. 12(36), p. 1–12. doi: 10.1126/sciadv.aec7585.
• Strand, Marius André; To, Thu-Hien; Tørresen, Ole Kristian; Fullmer, Sarah; Ferrari, Giada & Skage, Morten [Show all 9 contributors for this article] (2026). The origin of the octoploid cloudberry (Rubus chamaemorus) genome is the result of multiple and complex polyploidization events. Journal of Heredity. ISSN 0022-1503. 117(4), p. 822–833. doi: 10.1093/jhered/esag028. Full text in Research Archive
• Taylor, Victoria E.; Piasecki, Alison; Straume, Eivind Olavson & Meckler, A. Nele (2026). Divergent deep-sea temperatures in the Pacific and Atlantic during the onset of Antarctic glaciation. Nature Geoscience. ISSN 1752-0894. doi: 10.1038/s41561-026-02106-x. Full text in Research Archive Show summary

  Approximately 34 million years ago at the Eocene–Oligocene transition, Earth cooled sufficiently to sustain a large-scale Antarctic ice sheet. Our understanding of this climatic pivot point relies heavily on oxygen isotope records from deep-sea dwelling benthic foraminifera (δ18Ob), which document a globally synchronous increase, interpreted to reflect a combination of deep-sea cooling and ice-sheet growth. Here we present benthic foraminiferal clumped isotope-derived deep-sea temperature records from two ocean basins, spanning the Eocene–Oligocene transition. Our records from the equatorial Pacific and North Atlantic exhibit divergent temperature behaviour, in contrast to similar δ18Ob signals, with earlier Pacific and later Atlantic cooling compared with the δ18Ob increase. These differences are probably masked in the δ18Ob records by contrasting salinity gradients required to maintain similar densities. A reversed interbasin temperature gradient relative to today, with an overall cooler deep North Atlantic, suggests a very different deep-ocean structure, with potentially two different southern-sourced deep-water masses. The divergent properties of these two water masses may reflect different interactions between the temporally and spatially variable early cryosphere and deep-water formation regions, indicating a direct influence of the cryosphere on deep-water properties.

• Bellini, Natália Karla; Nachtigall, Pedro Gabriel; Lima, Pedro Leonardo Carvalho de; Silva, Herbert Guimarães de Sousa; Pires, David da Silva & Souza, Vinicius Carius de [Show all 12 contributors for this article] (2026). First genome-wide centromere map of Trypanosoma cruzi suggests linear and 3D compartment boundaries and spatial clustering. BMC Genomics. 27. doi: 10.1186/s12864-026-13072-4. Full text in Research Archive Show summary

  Background Trypanosoma cruzi, the etiological agent of Chagas disease, possesses a highly repetitive genome that has historically hindered high-quality assembly and structural characterization. Despite significant advances in assembling T. cruzi genomes, major gaps remain. Among these, the complete repertoire of centromeric sequences has remained elusive, representing a critical missing piece in our understanding of chromosome structure and inheritance. Results Here, we generated high-coverage Hi-C (genome-wide chromosome conformation capture) data for the widely used T. cruzi Dm28c strain improving its genome assembly by scaffolding contigs and producing a more contiguous and accurate genome. To investigate centromere organization, we performed ChIP-seq using the mNeonGreen-myc-tagged kinetochore proteins KKT2 and KKT3, resulting in the identification of 33 KKT-enriched peaks across 27 scaffolds. These peaks were located in regions enriched in retrotransposable elements, particularly L1Tc and VIPER, near strand switch regions, areas of high GC content, and in 51% of the cases at the transitional regions between conserved genes and virulence-factor multigene families. Notably, Hi-C analysis shows that candidate centromeric regions are frequently positioned between genomic domains with distinct 3D interaction profiles suggesting that they may contribute to genome compartmentalization, and frequently engage in 3D spatial clustering, suggesting a role in higher-order nuclear architecture. Conclusion Overall, our study provides a high-quality reference genome for the Dm28c strain, presents the first genome-wide centromere map in T. cruzi, and offers novel insights into centromere-mediated 3D genome organization.

• Kibaja, Mohamed Julius; Ndimuligo, Sood Athumani; Moore, Jim; Davenport, Tim R.B.; Nahonyo, Cuthbert L. & Stenseth, Nils Christian [Show all 7 contributors for this article] (2026). An arboreal and folivorous monkey, the endangered ashy red colobus (Piliocolobus tephrosceles) exists across dry deciduous Savanna woodland in Tanzania. Global Ecology and Conservation. 69. doi: 10.1016/j.gecco.2026.e04323. Full text in Research Archive
• Hermansen, Johanne Uthus; Kong, Weikaixin; Brodersen, Andrea M; Yanping, Yin; Urban, Aleksandra & Rein, Idun Dale [Show all 25 contributors for this article] (2026). A functional prognostic model predicts progression‐free survival in patients with relapsed chronic lymphocytic leukemia treated with ibrutinib + venetoclax. HemaSphere. 10(9). doi: 10.1002/hem3.70467. Full text in Research Archive Show summary

  Targeted therapies have improved outcomes for patients with chronic lymphocytic leukemia (CLL); yet, not all achieve durable responses. Existing prognostic models, developed for chemoimmunotherapy, have limited predictive value for newer targeted combinations. Here, we used data from a randomized phase II clinical trial to identify predictors of progression‐free survival (PFS) in response to Bruton tyrosine kinase (BTK) + B‐cell lymphoma 2 (Bcl‐2) inhibitor combination therapy. We studied the functional, genetic, and clinical characteristics of patients with relapsed/refractory (R/R) CLL treated with ibrutinib + venetoclax in the VISION/HO141 clinical trial (NCT03226301). Ex vivo drug sensitivity testing, (phospho)protein profiling, and immunophenotyping were performed on baseline peripheral blood mononuclear cells from 177 patients. Ex vivo drug sensitivity correlated with clinical responses to single‐agent therapies. (Phospho)protein patterns reflected intracellular pathway activity and predicted ex vivo drug sensitivity. Using stringent feature selection and regularized ridge regression to prevent overfitting, we integrated functional, genetic, and clinical data sets and identified six features—sensitivity to VEGFR‐2‐, JAK1/2 + Bcl‐2‐, and BTK + PI3K‐inhibitors; phosphorylation ratios of Bcl‐2:BTK and p90RSK:PLCγ2; and frequency of CD8 + T cells—that together outperformed the International Prognostic Index for CLL (CLL‐IPI) and other clinical scores in predicting PFS. These findings demonstrate that a prognostic model based on the functional features of CLL cell signaling and interaction with the microenvironment has the potential to improve upon conventional prognostic scores, warranting further clinical validation also in the frontline setting.

• Labun, Kornel; Rio, Oline Eriksen; Dahal-Koirala, Shiva; Komisarczuk, Anna Zofia; Valen, Eivind & Haapaniemi, Emma Maria (2026). SNIPSNP: precision design of CRISPR/Cas9 knock-in reagents for variant correction and disease modeling. Nucleic Acids Research (NAR). ISSN 0305-1048. 54(W1), p. W145–W153. doi: 10.1093/nar/gkag409. Full text in Research Archive Show summary

  We present SNIPSNP (crisprtools.org/snipsnp), a comprehensive bioinformatics pipeline for designing experiments for CRISPR-induced homology-directed repair (HDR). The tool addresses the critical challenge of Cas9 re-cleavage by simplifying the selection of “blocking” silent variants that are effective at inhibiting RNP binding upon donor-templated editing. SNIPSNP handles complex edits, including indels, and uses multi-objective optimization to balance editing efficiency with biological safety. From user-defined wild-type and desired HDR alleles, the pipeline identifies candidate guides, annotating them with integrated efficiency scores and genome-wide off-target assessments. Uniquely, SNIPSNP evaluates guide binding against the post-edit genome to determine whether the therapeutic variant alone disrupts repeated Cas9 recognition. When necessary, it introduces synonymous blocking variants, prioritizing PAM and seed regions to minimize re-cleavage probability and editing of the wild-type (WT) allele when editing heterozygous variants. All candidate modifications undergo safety profiling and prioritization of known benign variants from dbSNP. We experimentally validated SNIPSNP and benchmarked it on pathogenic inborn error of immunity variants in primary patient T-cells. Across loci, SNIPSNP-designed templates outperform standard “correction-only” strategies, demonstrating enhanced precision editing, and reduced re-cleavage, establishing SNIPSNP as a robust platform for genome editing and disease modeling.

• Hornslien, Karina Stensland; Myking, Ida Velle; Bjerkan, Katrine Nergård; Krabberød, Anders Kristian; Miller, Jason Rafe & Grini, Paul (2026). Parent-of-origin specific allelic expression in outbreeding Arabidopsis arenosa identifies antagonistic parental enrichment in protein degradation pathways. New Phytologist. ISSN 0028-646X. doi: 10.1111/nph.71551. Full text in Research Archive
• Mellacher, Patrick & Plakolb, Simon (2026). Global inequality in vaccine access, mortality and economy: An agent-based exploration. Journal of Economic Behavior and Organization. ISSN 0167-2681. 250. doi: 10.1016/j.jebo.2026.107762. Full text in Research Archive Show summary

  We develop an agent-based model to study the economic and public health impact of global vaccine inequality. Our model contains two world regions (higher-income vs. lower-income) and captures the co-evolution between economic activity, the spread and evolution of a hypothetical novel pandemic virus, and public health responses. We calibrate and estimate the model parameters empirically with data from the COVID-19 pandemic to capture the economic and social response to pandemic viruses in both regions. Our simulations suggest that vaccine inequality can drastically exacerbate inequality in mortality in the two regions. This is because the lower-income region suffers from drastically increased mortality, while the higher-income region generally only experiences a small (if any) decrease in mortality in most simulations. However, vaccine inequality harms both regions economically. This is driven by the fact that severe vaccine inequality eliminates the prospect of eradicating a mutating virus. Any trade-off between mortality in higher- and lower-income regions can be mitigated by increasing the production of vaccine doses. Furthermore, our analysis reveals that the higher-income region benefits economically from paying for increased vaccine production.

• Herrera, Melissa Sánchez; Martino, Frasella De; Sanabria, Pablo Emilio Realpe & Rebolledo, Emilio Realpe (2026). New high elevation cockroach, Lamproblatta neuque sp. nov. (Dictyoptera: Lamproblattidae) from Colombia. Zootaxa. ISSN 1175-5326. 5782(2), p. 313–329. doi: 10.11646/zootaxa.5782.2.4. Full text in Research Archive Show summary

  We describe Lamproblatta neuque sp. nov., a new cockroach species from high-elevation forest patches (~2600 m a.s.l.) near Bogotá, Colombia. This species is distinguished by a W-shaped ninth tergite, unique morphology of the subgenital and supra-anal plates, and the structure of the ootheca. Males also exhibit a small tergal gland on the supra-anal plate, expanding the known variation of this feature within Lamproblattidae. The discovery of L. neuque sp. nov. at an unusually high elevation highlights the persistence of biodiversity in remnant Andean forest habitats. Our findings underscore the need for a taxonomic revision of Lamproblattidae integrating morphological and genetic evidence.

• Zhou, Youbing; Cui, Jifa; Chen, Wenwen; Wu, Nan; Newman, Chris & Li, Juncheng [Show all 14 contributors for this article] (2026). Compound Ecoclimatic Events: The Long-Term Recovery of Conservation-Priority Mammals After an Extreme Ice Storm Event Was Promoted by the Alleviation of Poaching. Global Change Biology. ISSN 1354-1013. 32(9). doi: 10.1111/gcb.71084. Full text in Research Archive
• Vu, Ngoc Anh; Le, Minh Hoang; Lu, Tuan Anh Hoang; Luu, Hoang Viet; Doan, Nam X. & Truong, Kiem N. [Show all 7 contributors for this article] (2026). Timing of marine heatwave exposure across developmental stages modulates the copper effects on fitness traits in tropical copepods. Frontiers in Marine Science. 13, p. 1–12. doi: 10.3389/fmars.2026.1843680. Full text in Research Archive
• Hich, Tran Vi; Dinh, van Khuong; Cuc, Nguyen Thi Kim; Giang, Nguyen Thi Thuy; Phuong, Pham Thi Dan & Minh, Nguyen Cong [Show all 7 contributors for this article] (2026). Chitosan nanoparticles derived from molted shrimp shells as biodegradable adjuvants for Vibrio harveyi vaccination in Asian sea bass (Lates calcarifer). Regional Studies in Marine Science. 102. doi: 10.1016/j.rsma.2026.105385. Full text in Research Archive
• Plakolb, Simon & Hiden, Raffael (2026). Digital twins and systemic acceleration: insights from Luhmann’s sociological perspective. Frontiers in Sociology. 11. doi: 10.3389/fsoc.2026.1884848. Full text in Research Archive Show summary

  The digital age has brought about many hypes about new technology of which digital twins are among the most recent. Techno-optimistic thought proclaims them to bring about a revolution in societal management. We interrogate Luhmann’s sociology about the relationship between a social system and (its) digital twin(−s). In doing so we discover that common definitions of digital twins do not go beyond long-established technologies. If a digital twin is a computer model that is fed by information of the physical system which it influences in some feedback loop, to Luhmann every computer model is one. Yet, the term points to the apparent necessity to baptize an observable difference. We identify the latest and ongoing acceleration of integrated digital systems as this difference that makes a difference. This systemic acceleration, the maximization of the velocity of self-reference, builds the focal point in our discussion of looming changes. We think that digital twins encode a power relationship. Only if society remains in control of the modes of selection can a digital twin foster its second-order observation. To this end, the engineering derived notion of a direct cybernetic wire that connects the digital twin to the physical must be replaced with a mechanism for structural coupling. A social digital twin can then act as a digital mirror that enables an immediate, radicalized second-order observation. Thus, digital twins are in our understanding the epitome of the accelerative effect that digitalization has on society.

• Arañó-Ansola, Javier; Galán-Luque, Inés; Domènech, Marc; Rico-Martín, Laura; Moody, Edmund R.R. & Suresh, Megha [Show all 11 contributors for this article] (2026). Evaluating 18S Phylogenetic Placement Accuracy to Uncover Hidden Diversity in Non-Bilaterian Animals. Environmental DNA. 8(4), p. 1–15. doi: 10.1002/edn3.70350.
• Baalsrud, Helle T; Tørresen, Ole K; Danneels, Bram; Ferrari, Giada; Tooming-Klunderud, Ave & Skage, Morten [Show all 12 contributors for this article] (2026). Chromosomal fusions shaped the genome of the greater hornwrack bryozoan (Flustra foliacea) (Linnaeus, 1758). Journal of Heredity. ISSN 0022-1503. 117(4), p. 750–760. doi: https:/academic.oup.com/jhered/article/117/4/750/8497176. Full text in Research Archive Show summary

  The phylum Bryozoa is an understudied, yet commonly occurring, globally distributed bilaterian metazoan organismal group. They have a colonial lifestyle and an evolutionary history that spans at least 480 million years but likely longer. Despite their contentious phylogenetic affinities among metazoans, disproportionately few genomic investigations have been performed thus far. Here, we describe the first chromosome-level genome assembly of an individual Flustra foliacea colony belonging to the order Cheilostomatida, collected in southern Norway. The haplotype-resolved assembly of F. foliacea contains two pseudo-haplotypes spanning 956 megabases and 880 megabases, respectively. Both assemblies are highly complete both in terms of scaffolding (>90% of sequences placed in eight autosomal chromosomal pseudomolecules), and gene content (BUSCO completeness scores >90%). We also present gene and repeat annotations of the two assemblies. A comparison of our newly sequenced F. foliacea with five previously published bryozoan genomes supports the hypothesis that the group has undergone extensive genome rearrangements. This includes multiple chromosomal fusions in F. foliacea since their split with other cheilostome bryozoans. These fusions were enriched with long terminal repeat retrotransposons, highlighting the complex interplay between genome organization and genomic repeats. Our study contributes to a deeper understanding of bryozoan genome evolution and the role of repeats in metazoan genome organization.

• Nothnagel, Patrizia Maria Christiane; Meslin, Paul-Arthur Richard; Wik, Jonas Aakre; Dufour, Damien; Strøm, Yunna Erika & Bjørås, Magnar [Show all 11 contributors for this article] (2026). Transient SUMOylation inhibition in human pre-adipocytes stably imprints a transcriptional beiging fate. Nucleic Acids Research (NAR). ISSN 0305-1048. 54(6), p. 1–22. doi: 10.1093/nar/gkag232. Full text in Research Archive Show summary

  SUMOylation regulates chromatin states and transcriptional programs that preserve cellular identity, yet how perturbation of the SUMOylation pathway impacts adipocyte plasticity remains unclear. Here, we show that brief pharmacologic inhibition of SUMOylation in human pre-adipocytes using TAK-981 primes stable de novo beige differentiation in the presence of the PPARG agonist rosiglitazone. Transient TAK-981 exposure produces changes in the transcriptome and metabolism of mature adipocytes, including robust induction of canonical beiging markers like UCP1 and increased mitochondrial respiration. Mechanistically, ATAC-seq and RNA-sequencing revealed immediate chromatin remodeling and early mobilization of CEBP family members, followed by stable activation of CEBPA and PPARG regulatory networks. ChIP experiments demonstrated loss of H3K27me3 and gain of H3K27ac at PPAR response elements at thermogenic enhancers, and increased PPARG occupancy across the UCP1 regulatory unit. This mechanism is enforced by enhanced cAMP-PKA-p38 signaling and stabilization of beiging transcription activators. We propose that transient relief of SUMO-mediated repression unlocks dominant regulatory units, notably the UCP1 enhancer cluster, producing a monomorphic reprogramming toward adaptive thermogenesis. These findings identify SUMOylation as a reversible epigenetic barrier to adipocyte beiging and suggest that temporally controlled SUMO pathway inhibition combined with PPARG activation could be exploited to modulate adipose tissue thermogenic capacity.

• Cobb, Lauren Louise; Sydenham, Markus A. K.; Nielsen, Anders & Star, Bastiaan (2026). Significant fine-scale population differentiation in two common bumblebee species (B. pascuorum and B. lapidarius) detected in Northern Europe. Heredity. ISSN 0018-067X. p. 1–14. doi: 10.1038/s41437-026-00873-2. Full text in Research Archive Show summary

  Bumblebees are keystone pollinators which facilitate the reproduction of a wide range of wild and agricultural plants. Their abundance and diversity have been severely reduced by anthropogenic stressors such as widespread land-use change and habitat fragmentation. However, we lack a comprehensive understanding of population structure and local adaptation in bumblebees inhabiting human-altered landscapes. Here, we discover significant fine-scale (e.g. ~300 km) population structure within two common bumblebee species, Bombus lapidarius and Bombus pascuorum, by analysing whole genome data of 106 specimens from 7 sites in northern Europe. While the observed population structure is largely associated with natural oceanic barriers, we also detect significant divergence between populations sampled from anthropogenic landscapes which are not separated by such barriers. Furthermore, whereas genetic divergence in B. lapidarius is spread relatively evenly across the genome, divergence in B. pascuorum is concentrated within several megabase-sized genomic regions—including a putative chromosomal inversion – which may underlie well-known colour polymorphisms across its range. Our observations reveal a distinct genomic architecture underlying population structure within these bumblebee species, and highlight the necessity of increasing our understanding of bumblebee connectivity to design optimal bumblebee conservation strategies.

• Beek, Nienke van; Bargheet, Ahmed; Jian, Ching; Noordzij, Hanna Theodora; Ponsero, Alise & Pettersen, Veronika K. [Show all 7 contributors for this article] (2026). Metagenomic survey of pathogen prevalence in the infant gut. Scientific Reports. 16(1). doi: 10.1038/s41598-026-47440-7. Full text in Research Archive
• Adélaïde, Morgane; Yarava, Jayasubba Reddy; Lindemann, Florian; Abbas, Massilia; Cremer, Nils & Gerland, Lisa [Show all 14 contributors for this article] (2026). Structure and Dynamics of Porin Loops in Asymmetric Outer Membranes of E. coli. Chemistry - A European Journal. ISSN 0947-6539. doi: 10.1002/chem.71575. Full text in Research Archive Show summary

  Biological membranes are usually asymmetric lipid bilayers that possess an oligosaccharide coat on the outside into which loops of transmembrane proteins extend. Structurally, the protein-bilayer interface is not well explored. As a paradigmatic example, we examine the structure of the bacterial outer membrane protein G (OmpG) expressed into E. coli outer membranes (OM). We investigate two strands of the β-sheet and loops 6 and 7 that extend into the lipopolysaccharide (LPS) layer and which are involved in pore opening (pH > 6.0) and closing (pH < 6.0). Previous x-ray crystallography studies described these loops as well-ordered, whereas solid-state NMR described them as fully disordered, largely due to a lack of signal. Here, solid-state NMR measurements of OmpG in OM vesicles at 1.2 GHz 1H frequency now yield extended sets of cross peaks for His and Trp residues. Two alternative conformations are observed for two His residues, which are likely H231 and H261. Trp sidechain cross peak intensities in cross polarization spectra are in agreement with an increase of conformational freedom toward the surface. The oligosaccharide layer appears to protect the loops while promoting flexibility and multiple conformations. Our investigation highlights the importance of structural investigations in a quasi-native environment.

• Nilsen, Jeannette; Sand, Kine M. K.; Al-Khabbaz, Hana J.; Ligtenberg, Lennart Maximilian van; Mester, Simone & Mathiesen, Line [Show all 28 contributors for this article] (2026). Fusion of IgG antibodies to albumin inhibits transport across the placenta. Science immunology. 11(122). doi: 10.1126/sciimmunol.aee5151. Full text in Research Archive Show summary

  Immunoglobulin G (IgG)–based monoclonal antibodies are effective therapies for cancer, autoimmune diseases, and migraine. However, they are actively transported across the placenta by the neonatal Fc receptor (FcRn), limiting their use during pregnancy. Using mouse models and an ex vivo human placental perfusion system, we show that although FcRn binds albumin independently of IgG, albumin is not transported to the fetus in mice or across human placental tissue. Fusion of IgG to albumin markedly reduced transplacental transport in both models while preserving the prolonged plasma half-life conferred by FcRn. Similarly, fragment antigen–binding fragments fused to engineered albumin with enhanced FcRn binding showed minimal fetal exposure. In a mouse model of fetal and neonatal alloimmune thrombocytopenia, albumin fusion of an anti–human platelet antigen IgG reduced fetal antibody transfer and attenuated thrombocytopenia in the offspring. These findings identify albumin as an attractive fusion partner for biologics intended to minimize fetal exposure during pregnancy.

• Jourdain, Eve Marie; McKinney, Melissa A.; Remili, Anaïs; Andvik, Clare Margaret; Fagerlund, Carl Johan Ludwig & Karoliussen, Richard [Show all 8 contributors for this article] (2026). Advancing Amino Acid Isotope‐Inferred Trophic Ecology in an Apex Predator: Insights From a Data‐Rich Killer Whale Population. Ecology and Evolution. 16(8), p. 1–16. doi: 10.1002/ece3.74121. Full text in Research Archive Show summary

  Amino acid‐specific nitrogen isotope analysis (δ 15 N‐AA) is increasingly used to infer trophic ecology, yet remains poorly validated in marine predators. We analyzed bulk tissue δ 15 N ( 15 N/ 14 N) and δ 13 C ( 13 C/ 12 C), and δ 15 N‐AA in 105 skin samples collected from individually identified Norwegian killer whales between 2017 and 2023. Forty‐two individuals with best documented diets in 2010–2023, based on field observations and corroborated by mercury concentrations and bulk tissue δ 15 N values in skin, provided reference diet groups against which δ 15 N‐AA‐derived hypotheses were tested: Fish‐only (100% fish prey; n  = 15), Intermediate mixed diet (~10% mammalian prey in addition to fish; n  = 14), and Top mixed diet (~50% mammals, 50% fish prey; n  = 13). Univariate and multivariate approaches identified diet as the primary driver of δ 15 N variation across individual amino acids and multivariate isotopic space, whereas sex and life stage had little effect. However, substantial inter‐individual variation remained unexplained and appeared to reflect metabolic processes. Metrics δ 15 N ΣTrophic—ΣSource (δ 15 N difference between the sum of trophic amino acids and the sum of source amino acids) and isotopic difference between glutamic acid/glutamine (Glu) and phenylalanine (Phe) (δ 15 N Glu–Phe ) successfully identified Top mixed diet whales but lacked the sensitivity to identify Intermediate mixed diet individuals, whilst δ 15 N values of Threonine showed no relationship with trophic position. Proline (Pro) and Phe used as trophic‐source pair provided the first plausible δ 15 N‐AA‐derived trophic position estimates for killer whales and performed better than bulk isotope‐derived trophic position when a priori knowledge was not available. Multivariate clustering of δ 15 N‐AA data complemented trophic position estimates by resolving finer‐scale dietary variation occurring within trophic levels.

• Wei, Maohong; Lu, Xueqiang; Li, Hongyuan; Zhu, Lin; Zhu, Jiyou & Stenseth, Nils Christian [Show all 8 contributors for this article] (2026). Water availability regulates abrupt shifts in global terrestrial vegetation productivity by reducing resilience. Proceedings of the Royal Society of London. Biological Sciences. ISSN 0962-8452. 293(2068), p. 1–12. doi: 10.1098/rspb.2025.3118. Full text in Research Archive Show summary

  Abrupt shifts in vegetation productivity induced by environmental change profoundly affect ecosystem functions and services, such as carbon sequestration, biodiversity maintenance and climate regulation, yet their long-term global patterns and underlying drivers remain insufficiently understood. In this study, abrupt shifts in vegetation productivity were identified using two independent long-term satellite datasets, and early warning signals were assessed through ecosystem resilience. The main drivers of resilience decline were further examined across land-cover, climate and human-activity dimensions. The results showed that negative abrupt shifts were predominantly concentrated in high northern latitudes and equatorial regions, and that both negative and positive abrupt shifts displayed distinct increasing trends after 2002. A sharp decline in ecosystem resilience was also detected during the 4 years preceding abrupt shifts. Changes in water availability were identified as the primary factor contributing to the reduced resilience of global ecosystems, as evidenced by the driver trajectory, generalized additive models and convergent cross-mapping methods. This study provides insight into the pervasive occurrence of abrupt shifts in vegetation productivity and the discernible impact of climate change. When projecting vegetation dynamics under future climate change, it is essential to consider the significant uncertainties associated with abrupt shifts.

• Koch, Thomas Lund; Ferrari, Giada; Sumanam, Sunita B; Salcedo, Paula Flórez; Watkins, Maren & Chase, Kevin [Show all 13 contributors for this article] (2026). From neuropeptides to toxins: illuminating the origins of venom complexity in cone snails. Molecular Biology and Evolution (MBE). ISSN 0737-4038. 43, p. 1–20. doi: 10.1093/molbev/msag206. Full text in Research Archive Show summary

  New genes and gene functions are key drivers of evolutionary innovation. Venomous animals, such as cone snails, provide striking examples of gene innovation, yet the mechanisms by which toxins arise remain poorly understood. Using the Conus textile genome, we uncover how neuropeptide genes were recruited into the venom and neofunctionalized as doppelgänger toxins. We identify over 20 independent recruitment events that evolved dynamically across the Conus lineage. Rather than arising from ohnologs of a whole-genome duplication event ∼200 mya, these toxins evolved through diverse mechanisms, including exon shuffling, alternative splicing, and ectopic recombination, often facilitated by lineage-specific transposable elements. Our findings reveal a dynamic interplay between genome architecture and molecular innovation, offering broad insight into the evolution of complex gene repertoires in venoms and beyond.

• Araya, Robin Aasegg; Maurstad, Marius Filomeno; Wilson, David T; Rash, Lachlan D; Mobli, Mehdi & Jakobsen, Kjetill Sigurd [Show all 7 contributors for this article] (2026). Ancient origin and dynamic evolution of bivalent spider toxins. Molecular Biology and Evolution (MBE). ISSN 0737-4038. 43(5). doi: 10.1093/molbev/msag076. Full text in Research Archive Show summary

  Bivalent peptide toxins comprising 2 cysteine-rich domains have evolved from single-domain precursors on multiple occasions in animal venoms, resulting in enhanced molecular target selectivity and avidity. Although bivalent toxins are emerging as prevalent in animal venoms, the genomic and evolutionary processes driving the transitions between single- and multi-domain architectures remain poorly understood. Here, we investigated the evolution of bivalent inhibitor cystine knot (ICK) toxins in spider venom. We first generated a genome assembly of the tree-dwelling funnel-web spider Hadronyche cerberea, revealing a massive expansion of ICK toxin-encoding genes, including the bivalent π-hexatoxin-Hc1a. All ICK toxin genes share a conserved 3-exon structure, flanked by transposable elements (TEs) that may have facilitated gene expansion. This gene structure is shared by the Hc1a subfamily, where the entire mature bivalent toxin is encoded by the third exon. Leveraging de novo transcriptome assemblies from 86 spider species along with venom proteomic data, we show that bivalency in the Hc1a subfamily is of ancient origin and evolved via intra-exonic duplication not involving introns. This was followed by domain expansion and recurrent domain losses mediated by point mutations, deletions, and unequal crossing-over facilitated by high interdomain sequence similarity. In contrast, the bivalent toxin DkTx from Cyriopagopus schmidti is confined to a small group of tarantulas, where it appears to have evolved once, with subsequent domain losses potentially linked to TE activity. Our findings reveal that singular events of domain duplication can give rise to complex, asymmetrical evolutionary trajectories shaped by gene instability and selective retention of functional domains.

• Bergström, Ann Kristin; Paltsev, Aleksey; Hessen, Dag Olav; Kortelainen, Pirkko; Vuorenmaa, Jussi & Wit, Heleen de [Show all 15 contributors for this article] (2026). Global Change Reshapes Northern Lakes Towards Browner, More Nutrient-Depleted and Nitrogen-Limited Conditions With Contrasting Impacts on Phytoplankton Biomass. Global Change Biology. ISSN 1354-1013. 32(7), p. 1–19. doi: 10.1111/gcb.71008. Full text in Research Archive Show summary

  Global change is altering trade-offs between light and nutrient availability in northern lakes, with implications for biogeochemical cycling and ecosystem functioning. Using 29 years (1991–2019) of long-term monitoring from 169 Fennoscandian natural lakes, we quantified spatiotemporal change in browning (total organic carbon, TOC), dissolved inorganic nitrogen (DIN), total phosphorus (TP), and stoichiometry (TOC:TP and DIN:TP). We then related these trajectories to co-occurring trends in air temperature, precipitation, and atmospheric nitrogen (N) and sulfur (S) deposition to evaluate how climate change and deposition recovery jointly reconfigure lake chemistry across subregions. TOC increased widely and DIN declined across most lakes, whereas TP trends were mixed, producing a pervasive rise in TOC:TP and decline in DIN:TP over time. Mixed linear models indicated that TOC increases were most often associated with declining S deposition and increasing precipitation, while DIN was generally positively related to N deposition, with additional subregional roles for temperature and precipitation. As browning coincided with declining DIN:TP, lakes shifted toward darker conditions with greater prevalence of nitrogen and phosphorus co-limitation and nitrogen limitation relative to phosphorus limitation. In a Swedish subset of 74 lakes, chlorophyll-a trends were heterogeneous among subregions, indicating context-dependent biomass responses rather than a uniform phytoplankton signal. Together, these results show that ongoing climate change and reduced atmospheric deposition are reshaping carbon–nutrient coupling and nutrient-limitation regimes across northern lakes, with consequences for future primary production and energy transfer to higher trophic levels.

• Tefera, Eskinder Belay; Stenseth, Nils Christian; Alemu, Tibebu; Gemeda, Dessalegn Obsi & Gutema, Tariku Mekonnen (2026). Mutualistic human-bird interactions: Honeyguides and vultures’ unique symbioses with indigenous communities in Southwestern Ethiopia. European Journal of Wildlife Research. ISSN 1612-4642. 72(4), p. 1–14. doi: 10.1007/s10344-026-02117-4. Full text in Research Archive
• Lettenmaier, Ludwig; Cadotte, Marc W.; Dittrich, Sebastian; Pierick, Kerstin; Ammer, Christian & Bradler, Pia M. [Show all 15 contributors for this article] (2026). Contrasting direct and indirect effects of roe deer on herb layer vegetation in gaps and closed canopies. Journal of Ecology. ISSN 0022-0477. 114(6). doi: 10.1111/1365-2745.70382.
• Nowicki, Robynne; Gabrielsen, Geir W.; Borgå, Katrine; Søreide, Janne & Varpe, Øystein (2026). Seasonality and water masses shape energetics of a high Arctic fish: quantifying energy density and condition indices. Marine Ecology Progress Series. ISSN 0171-8630. 786. doi: 10.3354/meps15150. Full text in Research Archive Show summary

  Seasonal life history decisions and environmental factors shape energetics over annual cycles. We quantified seasonal energy density of polar cod Boreogadus saida , a central predator and prey in the Arctic marine food web. We collected individuals from Atlantic and polar waters in the Barents Sea, to assess the impact of seasonality and water masses on energy density (kJ g -1 wet weight (WW)). Additionally, we compared energy density to 4 condition indices (Fulton’s, residual and hepatosomatic indices, and percent dry weight) to test their accuracy as energetic proxies for polar cod. Energy density varied seasonally and was lower in Atlantic waters. In polar waters, energy density was lowest in April/May, whereas seasonal variation was weaker in Atlantic waters. Energy density was highest in December in both water masses, although not much higher than March in polar water. Differences between water masses were seasonal, greatest in March (Atlantic: 4.07 ± 0.53 kJ g -1 WW; polar: 5.77 ± 0.62 kJ g -1 WW) and negligible in December (5.66 ± 0.83 and 5.86 ± 0.62 kJ g -1 WW, respectively). Percent dry weight best represented energy density, while Fulton’s and residual (derived from WW) indices were poorly correlated to energy density. Our results show that seasonality and environmental factors shape energetics, and that energy proxies must be carefully selected to accurately represent the energetic status of an organism. Our seasonal resolution highlights potential ‘critical windows’, when polar cod may be most vulnerable to stressors, whilst our spatial comparison provides insight into potential impacts of ongoing Atlantification.

• Suaste, Veronica; Presterud, Rebecca; Wennerström, Anna Berit; Wang, Heling; Zhang, Jianying & Lund, Solveig Osnes [Show all 16 contributors for this article] (2026). Transcriptional Profiling Shows Dampening of Interferon Gene Signatures by NAD Augmentation in Ataxia-Telangiectasia. International Journal of Molecular Sciences. ISSN 1661-6596. 27(13). doi: 10.3390/ijms27135652. Full text in Research Archive Show summary

  Ataxia-Telangiectasia (A-T) is a multisystem disorder caused by loss of A-T mutated (ATM) protein activity, characterized clinically by immunodeficiency and cerebellar ataxia. ATM is a master regulator of DNA damage responses and loss of ATM function is accompanied by persistent activation of PARP1 leading to depletion of intracellular NAD+ and dysfunction of a series of cellular signalling pathways dependent on NAD+, providing a mechanistic rationale for NAD+ augmentation therapy. We performed a clinical trial of NAD+ augmentation with nicotinamide riboside (NR) over 24 months in A-T patients where we observed improved coordination and eye movements in A-T patients. Here, by using peripheral blood mononuclear cells, we performed longitudinal transcriptome profiling to define molecular signatures of A-T and to assess pathway-level responses to NR supplementation. A-T patients exhibited reproducible transcriptomic alterations involving immune, vascular, and inflammatory pathways. NAD+ augmentation was associated with suppression of interferon response genes and modulation of networks correlated with neurological improvement. These findings establish systemic molecular signatures of A-T and identify potential blood-based biomarkers that reflect disease processes and therapeutic response, supporting the use of NAD+ augmentation as a disease-modifying strategy in A-T by dampening interferon signalling.

• Bieker, Vanessa Carina; Li, Siyu; Cerca, José; Battlay, Paul; Falahati-Anbaran, Mohsen & Sharma, Amit [Show all 22 contributors for this article] (2026). The genomic basis of adaptive leaf variation in the Galápagos giant daisies. Nature Communications. 17(1). doi: 10.1038/s41467-026-71865-3. Full text in Research Archive Show summary

  Scalesia (Asteraceae) is the largest endemic plant genus of the Galápagos archipelago and an example of adaptive radiation. While Scalesia species are highly varied in habit and morphology, most remarkable is their variety of leaf shapes, especially in the differential presence of leaf lobing/serration, a derived trait that evolved multiple times as a likely adaptation to the islands’ hot and dry equatorial climate. Using population-level genomic data from 396 individuals representing all 15 recognized Scalesia species, we characterize this young radiation (around 1 million years ago), and reveal that their substantial morphological divergence and ecological specialization are primarily based on shared genetic variation. To further elucidate the repeated adaptive evolution of leaf lobing in Scalesia , we integrate genomic and leaf morphometric data, with transcriptomes from different developmental stages, and conclude that leaf lobing evolved through diversifying selection. Natural selection occurs independently on different regulators in the pathway controlling development of adaxial-abaxial leaf polarity, highlighting the importance of the founder populations’ high genetic diversity maintained via allopolyploidy. Finally, our findings have implications for the conservation of Scalesia ’s threatened biodiversity, as unexpectedly high intra-specific genetic structure and long-term isolation among populations indicate widespread nascent speciation.

• Casillas, Nina; Petersen, Bent; Martin, Sarah Louise; Ophus, Kjeld Henrik; Bringsøe, Henrik & Brealey, Jaelle Caitlin [Show all 14 contributors for this article] (2026). Genome Scanning Reveals the Genetic Basis of a Color Pattern Morphotype in an Island Population of the European Adder (Vipera berus). Genome Biology and Evolution (GBE). 18(6). doi: 10.1093/gbe/evag144. Full text in Research Archive Show summary

  Color polymorphism is an important trait due to its role in defense strategies, feeding habits, environmental responses such as temperature regulation, and overall fitness. While the genetic basis of color polymorphism is well understood in mammals, it remains relatively understudied in nonavian reptiles. Vipera berus, the European adder, is the most widely distributed and northernmost terrestrial snake in the world. Similar to other European vipers, V. berus exhibits a range of dorsal color patterns spanning from zig-zag to complete melanism. However, a unique longitudinal dorsal stripe pattern was recently discovered in the isolated Gossa Island (∼45 km2) population of Norway, where ∼5% of snakes exhibit this distinct pattern instead of the common dorsal zig-zag pattern. In this study, we investigated the genetic basis of the unique phenotype observed on Gossa by combining low-depth whole-genome shotgun sequencing and pairwise FST genome scanning. We discovered a moderately sized, significantly differentiated genomic region containing five associated genes, including the premelanosome gene (PMEL) that encodes a well-known transmembrane glycoprotein that is a key component of melanosome organelles. We implicate a functionally relevant variant in the encoded premelanosome protein. Our results provide insight into the evolution and genetic basis of pigmentation of squamate reptiles using the unbiased approach of genome scanning, a method that has rarely been used in this context.

• Sim, Clarence Wei Hung; Walde, Marie; Strindberg, Hanna; Kaur, Avneet; Panse, Sophie Le & Gourvil, Priscillia [Show all 9 contributors for this article] (2026). Labyrinthula merlionensis sp. nov.: A Novel Labyrinthulid Infecting Marine Diatoms. Journal of Eukaryotic Microbiology. ISSN 1066-5234. 73(5). doi: 10.1111/jeu.70111. Full text in Research Archive
• Mjøen, Hedvig Elisabeth; Løken, Solveig Bua; Carlsen, Tor; Brysting, Anne Krag & Bjorå, Charlotte Sletten (2026). Resolving the Veratrum phylogeny in northern Fennoscandia by targeted sequencing. Taxon. ISSN 0040-0262. 75(4). doi: 10.1002/tax.70201. Full text in Research Archive Show summary

  The genus Veratrum comprises approximately 24 species from temperate and arctic North America and Eurasia. In Europe, Veratrum is mainly distributed in mountainous areas of central and southern Europe but is also locally abundant in coastal areas of north-eastern Finnmark, Norway. The taxon name for the Veratrum in Finnmark has over the years been disputed. Several names have been applied, including V. album, V. lobelianum, and various subspecies of these. Previous phylogenetic analyses of Veratrum based on Sanger sequences of the ITS region have lacked sufficient resolution to resolve the relationships within the genus. Furthermore, the Veratrum in Finnmark has not been included in any molecular phylogenetic analysis, leaving its relationship to other populations of Veratrum unknown. The aims of this study were therefore to place the Veratrum in Finnmark in a molecular phylogenetic context, assess if this group represents a separate taxon, and determine the appropriate nomenclature. We applied a target capture approach, using the Angiosperms-353 probe set, to obtain a multi-locus phylogenetic dataset. Our phylogeny reveals that the Veratrum in Finnmark are closely related to Veratrum populations in northern Finland and Russia. Northern European Veratrum resolves as a distinct clade and represents a distinct taxon separate from populations in central Europe. We propose the name V. album subsp. misae for the northern European Veratrum.

• Willoch-Allen, Katarina; Zhao, Zhi; Duran, Pilar Ayuda; Mikaeloff, Flora; Struyf, Nona & Österroos, Albin [Show all 13 contributors for this article] (2026). A multi-center study on the consistency of drug sensitivity testing in patients with acute myeloid leukemia. NPJ precision oncology. 10(1). doi: 10.1038/s41698-026-01480-4. Full text in Research Archive Show summary

  Clinical implementation of patient cell-based drug testing is hampered by inconsistencies and irreproducible results. Using linear mixed models and drug response data from four cohorts of patients with acute myeloid leukemia (n = 993 samples), we identified sources of variability in ex vivo drug sensitivity testing across the studies. We identified several experimental factors, including the time until sample was tested, the type of culture media and viability assay, which led to systematic differences in drug sensitivity profiles. We further investigated the effects of sample types (fresh or frozen) and disease status (diagnosis, relapse, or refractory), and observed that peripheral blood samples resulted in higher drug sensitivity levels, compared to those derived from bone marrow. Technical factors, such as the type of plate reader and centrifugation procedure, further contributed to the response variability depending on the chosen drug response metric. These factors need to be standardized for improved consistency in functional precision medicine studies.

• Rønneberg, Jørgen Dybevik; Hjeltnes, Martine; Krieger, Josephine; Elias, Joshua E.; Stensland, Maria & Holm, Kristian [Show all 15 contributors for this article] (2026). An epithelial GPR35 isoform supports tumor-associated transcriptional and metabolic phenotypes. FEBS Letters. ISSN 0014-5793. p. 1–23. doi: 10.1002/1873-3468.70423.
• Matovu, Paul; Ballesteros, Jesus Adrian Chimal; Bjorå, Charlotte Sletten; Nordal, Inger; Bulafu, Collins E. & Namaganda, Mary (2026). Distribution and Habitat Preferences of Chlorophytum (Asparagaceae) in Uganda. Journal of East African Natural History. ISSN 1026-1613. 115(4), p. 19–34. doi: 10.2982/028.115.401. Full text in Research Archive Show summary

  Field surveys on Chlorophytum in known and new localities were conducted across 70 districts within the four FTEA floral regions of Uganda between June 2019 and January 2020. The main aim was to map the distribution of taxa that existed in the country and document their habitats through a focused field survey. This was being done for the first time since the publication of the FTEA in 1997. Location coordinates and habitat characteristics were recorded, and voucher specimens collected for encountered plants. The study recorded 14 taxa consisting of 11 species. The U1 region recorded the highest species richness (11). Four species were recorded in U2, three in U4, and none in U3. Chlorophytum tordense, C. elgonense and C. blepharophyllum were the most frequent species while C. longifolium, C. gallabatense and C. miserum were the least frequent. Chlorophytum longifolium is reported here as a new record for Uganda. Chlorophytum species frequently occurred on sandy loams in undisturbed sites particularly in open woodland and wooded grassland habitats. Some eleven species previously recorded in the country were not encountered during this study, probably highlighting species extirpation.

• Atmore, Lane & Star, Bastiaan (2026). Beyond the scales: Marine archaeogenomics for the conservation and restoration of fisheries. Science. ISSN 0036-8075. 393(6810), p. 472–479. doi: 10.1126/science.aeg0333. Full text in Research Archive Show summary

  Protection and restoration of marine environments are essential for food security and climate change mitigation. Yet historical and archaeological research have shown that conservation and management often rely on arbitrary ecological baselines in ecosystems already shaped by long-term human impacts. Archaeogenomics, the combination of ancient DNA (aDNA) and whole-genome sequencing, provides invaluable insights into these impacts. Recent improvements in laboratory and computational techniques enable the assessment of past fish population dynamics, migration patterns, historical trade routes, long-term anthropogenic pressures, and responses to environmental change. This Review compiles aDNA research on archaeological fish remains, emphasizing studies from 2020 to 2025 that used whole-genome analysis to investigate historical fisheries and marine ecosystem change. We highlight the growing potential of archaeogenomics to inform restoration, conservation, sustainable fisheries management, and climate adaptation strategies worldwide.

• Andvik, Clare Margaret; Fagerlund, Carl Johan Ludwig; Jourdain, Eve Marie; Yuan, Bo; Haddad-Weiser, Gabrielle & Lyche, Jan Ludvig [Show all 9 contributors for this article] (2026). Comparing polychlorinated n-alkane occurrence and biomagnification with legacy contaminants in a killer whale food web. Environmental Research. ISSN 0013-9351. 306. doi: 10.1016/j.envres.2026.125367. Full text in Research Archive Show summary

  Polychlorinated n-alkanes (PCAs), the largest component of the commercial product chlorinated paraffins, have been used globally in increasing amounts since the regulations of legacy contaminants, such as polychlorinated biphenyls (PCBs). The bioaccumulative potential of PCAs compared to legacy contaminants is inconclusive, with limited data available for PCAs with carbon chain length ≤9 and ≥18, particularly in food webs which include mammalian top predators. Here, we analysed and compared PCAs of different carbon chain length (very-short: PCAs-C6-9 [vSCCPs], short: PCAs-C10-13 [SCCPs], medium: PCAs-C14-17 [MCCPs], and long: PCAs-C18-24 [LCCPs]), 57 legacy contaminants, and total mercury (Hg) in killer whales (Orcinus orca) from northern Norway (n = 59) and a range of fish and marine mammals. We found that legacy organic contaminants dominated in concentration and pattern in marine mammals (54–87%), whereas PCAs and Hg dominated in fishes (58–98%). A species' physiology (poikilotherm or homeotherm) influenced the food web magnification of several contaminants, with estimated trophic magnification factors (TMFs) underestimated in PCAs, and overestimated in PCB-153, p.p’-DDE and Hg, if unaccounted for. PCAs-C6-9 and PCAs-C10-13 had similar and low TMFs for poikilotherms and homeotherms, and similar to PCB-28 (TMF range: 1.9–2.4 [95% confidence interval 0.9–5.7]). PCAs-C14-17 and PCAs-C18-24, had high TMFs in poikilotherms (4.8 [1.3–18] and 4.6 [1.2–18], respectively), and no significant trophic magnification in homeotherms (1.0 [0.5–2.3] and 1.0 [0.4–2.8], respectively), with the opposite pattern for PCB-153 and p.p’-DDE. Our results indicate higher PCA concentrations and biomagnification potential in poikilotherms than homeotherms, which is likely due to lower biotransformation and elimination ability.

• Solbakken, Monica Hongrø; Tørresen, Ole Kristian; Tooming-Klunderud, Ave; Skage, Morten; Bakken, Torkild & Jakobsen, Kjetill Sigurd (2026). Loss of Major Histocompatibility Complex I and II Function in the Genome of Glacier Lanternfish Provides Insight Into Evolution of Vertebrate Immune Systems. Genome Biology and Evolution (GBE). 18(7). doi: 10.1093/gbe/evag154. Full text in Research Archive
• Sargautis, Domantas & Thiede, Bernd (2026). LC-MS peptide mapping of monoclonal antibodies using the mirror proteases trypsin and Tryp-N. Journal of Pharmaceutical and Biomedical Analysis. ISSN 0731-7085. 272. doi: 10.1016/j.jpba.2026.117361. Full text in Research Archive
• Cerca, José; Ravinet, Mark; Flagstad, Øystein; Rolandsen, Christer Moe; Strand, Olav & Tørresen, Ole Kristian [Show all 8 contributors for this article] (2026). Hybridization with wild individuals fuels reindeer feralization. Proceedings of the Royal Society of London. Biological Sciences. ISSN 0962-8452. 293(2075), p. 1–11. doi: 10.1098/rspb.2026.1226. Full text in Research Archive Show summary

  Domestication has profoundly influenced the development of human agriculture, and is characterized by intense artificial selection. Feralization occurs when domestic animals return to the wild. Although feralization does not fully reverse domestication traits, the selective pressures and evolutionary mechanisms driving it remain poorly understood. In northern Europe and Asia, wild, semi-domesticated and feral reindeer (Rangifer tarandus) populations coexist, offering a unique opportunity to study feralization. We studied genomic signatures of selection in semi-domesticated, feral and wild reindeer populations in Norway. Analysis of population structure confirmed historical records indicating the feral population formed a monophyletic clade that originated from neighbouring semi-domesticated reindeer. However, we also found evidence for excess allele-sharing between wild and feral reindeer, indicating hybridization between these lineages. Signatures of selection were identified using a top-down approach (orthologues of domestication candidate genes) and a bottom-up approach (FST and extended haplotypes). We found that candidate regions under selection have higher rates of excess allele-sharing between wild and feral populations. This provides the first evidence of reversed selection pressures during feralization in reindeer and reveals a link between selection and hybridization. Together, our findings suggest that hybridization likely promoted adaptive introgression during feralization. We discuss the implications of our findings for conserving the genetic integrity of endangered wild reindeer populations.

• Jonassen, Rune; Øverli, Øyvind; Hilland, Eva; Nilsen, Hilde; Esbensen, Qin Ying & Lirussi, Lisa [Show all 13 contributors for this article] (2026). Serotonin transporter polymorphism (5-HTTLPR) is associated with post-awakening cortisol measures in previous depression. Comprehensive Psychoneuroendocrinology. 27, p. 1–7. doi: 10.1016/j.cpnec.2026.100363. Full text in Research Archive Show summary

  Elevated cortisol levels have been linked to major depressive disorder (MDD), but cortisol dynamics vary substantially across individuals and clinical states. Genetic variation in the serotonin transporter polymorphism (5-HTTLPR) has been proposed as one contributor to differences in hypothalamic-pituitary-adrenal axis functioning. The present study examined associations between cortisol awakening measures and 5-HTTLPR genotype groups in individuals with a history of depression compared with healthy controls, and explored whether current depressive symptom severity was related to cortisol indices. A total of 108 individuals with a history of depression were genotyped and compared with 59 healthy controls. Participants completed structured diagnostic interviews and self-reported depressive symptoms. Salivary cortisol was sampled in the evening and at five consecutive timepoints after awakening (15-min intervals). Cortisol was analyzed using a linear mixed-effects model of repeated measures and by cortisol awakening response (CAR) summary indices: area under the curve with respect to ground (AUCg) and area under the curve with respect to increase (AUCi). Cortisol changed significantly over time, but there was no evidence that genotype groups differed in the overall cortisol timecourse. In CAR summary analyses, group differences were observed for AUCg, whereas AUCi did not show corresponding group differences. Regression analyses indicated that BDI-II was not associated with AUCg or AUCi after adjustment for covariates. These findings suggest that 5-HTTLPR-related differences, when present, may be more detectable in overall post-awakening cortisol output than in baseline-relative increase.

• Demeter, Katalin; Savio, Domenico; Kirschner, Alexander K T; Reischer, Georg H; Kolarevic, Stoimir & Parajka, Juraj [Show all 14 contributors for this article] (2026). Hydrological regime of a continental river system predicts bacterial macroecological patterns. The ISME Journal. ISSN 1751-7362. 19(1). doi: 10.1093/ismejo/wrag013. Full text in Research Archive Show summary

  Abstract Modeling bacterial dynamics in large river systems is crucial for predicting continental-scale ecosystem functioning under anthropogenic pressures. Although the River Continuum and Metacommunity concepts have provided theoretical frameworks, quantitative parameters necessary for microbial macroecological models remain scarce. Here, we present results from two whole-river surveys, conducted six years apart along 2600 km of the Danube River. Using bacterial secondary production, cell counts, and 16S ribosomal RNA (rRNA) gene amplicon sequencing, we quantified carbon, cell, phylotype, and diversity turnover along the river. Carbon incorporation per cell declined with water travel time by 6000–21 000 atoms per hour. Bacterial cells multiplied every eight days, resulting in four to six doublings during downstream transport. Growth responses at the level of individual phylotypes differed up to a hundredfold from these bulk community estimates. Bacterial diversity dynamics were dominated by phylotype turnover rather than phylotype loss. Turnover ranged from 0.92 to 0.96 along the river, indicating an almost complete replacement of phylotypes with 2%–11% of headwater-associated amplicon sequence variants (ASVs) persisting under base-flow conditions. Richness declined gradually downstream at a rate of ~0.13 ASVs per hour. Variations in bacterial secondary production, cell abundance, and observed ASVs were best explained by models combining hydrological and water quality parameters, whereas beta diversity followed a gradual development primarily structured by water travel time. Together, these results identify water travel time as the key integrative parameter governing microbial macroecological dynamics along large rivers, with environmental conditions fine-tuning local responses. These models can help predict changes in microbial diversity and functioning under anthropogenic alterations.

• Skotland, Tore & Sandvig, Kirsten (2026). Plasma membranes: does one model fit all? Trends in Cell Biology. ISSN 0962-8924. 36(7), p. 537–544. doi: 10.1016/j.tcb.2026.03.001. Full text in Research Archive Show summary

  Biological membranes consist of a lipid bilayer with a highly asymmetric distribution of lipids in the two leaflets. This asymmetry is maintained by enzymes whose activities depend on cytosolic ATP and Ca2+ concentrations. Recently, a new model for plasma membranes (PMs) was introduced. It is based on studies with human erythrocytes and suggests that there is a 50% overabundance of lipids with two hydrophobic chains in the cytosolic leaflet, compensated by the presence of three times more cholesterol in the outer leaflet. In this opinion article, we discuss the large differences in lipid composition between erythrocytes and other cell types, the assumptions used to reach the new membrane model, and whether this model would fit PMs of other cell types.

• Oeser, Julian; Kowalczyk, Rafał; Kuijper, Dries; Neumann, Wiebke; Reiner, Rudolf & Seidl, Rupert [Show all 65 contributors for this article] (2026). Increasing forest disturbance enhances habitat suitability for Europe’s large herbivores. Nature Ecology and Evolution. 10, p. 1273–1286. doi: 10.1038/s41559-026-03096-0. Full text in Research Archive Show summary

  Forest disturbances have increased in many regions, but how they impact habitat suitability for wildlife remains poorly understood. Here, by combining tracking data on 3,069 individuals of four ungulate species (European bison, moose, red deer and roe deer) with satellite-based maps, we perform a continental, multi-decadal assessment of large herbivore responses to forest disturbance. Despite strong intraspecific variation, all species show an increased selection of disturbed areas for ≥35 years after disturbance. Although the patterns closely reflect species-specific foraging strategies, all species selected more strongly for smaller disturbance patches, depending on the availability of alternative foraging habitats (grasslands and croplands). Model projections across the species’ range extents show positive but regionally varying effects of forest disturbances on habitat suitability between 2000 and 2023. Our findings indicate that forest disturbances can attract large herbivores and that the recent increase in forest disturbances improved habitat suitability for our study species across Europe, highlighting the importance of considering long-term disturbance-related dynamics for wildlife and forest management. Given expected future increases in disturbance, resulting habitat improvements could amplify conflicts with forestry, but also contribute to restoring large herbivores and their ecological functions.

• Baalsrud, Helle Tessand; Garmann-Aarhus, Benedicte; Enevoldsen, Emily Louise Gilbert; Krabberød, Anders Kristian; Dominik, Fischer, & Tooming-Klunderud, Ave [Show all 13 contributors for this article] (2026). Centromeric satellite expansion drives genome evolution in the snowy owl. Genome Biology. ISSN 1474-7596. doi: 10.1186/s13059-026-04175-y. Full text in Research Archive Show summary

  Comparative genomic studies in birds have revealed that bird genomes are relatively repeat-poor and stable in terms of karyotype, size, and gene synteny/collinearity compared to other vertebrates. One notable exception is the owls, with cytogenetic studies demonstrating large variations in karyotypes and the evolution of unusual centromeric satellite repeats in some species. However, there has so far not been an investigation into genome architecture and repeat landscape of owls. Here, we present a chromosome-level genome assembly for the snowy owl (Bubo scandiacus). We find that the repeat DNA content in the relatively large snowy owl genome (1.6&nbsp;Gb) is among the highest reported for any bird genome to date (28.34% compared to an average of ~ 10% in other birds). The bulk of the snowy owl genomic repeat landscape consists of extensive centromeric satellite arrays that form large contiguous blocks across multiple chromosomes. These arrays represent one of the largest centromeric satellite expansions reported in birds and are consistent with rapid turnover and amplification of centromeric repeats. Using gene collinearity analyses we show that the position of the centromeres are not homologous with chicken centromeres, and are located in regions with collinearity breaks to other bird genomes due to chromosomal rearrangements. Our results support rapid satellite turnover at lineage-specific centromeres, which could have played a role in centromeric drive, reproductive isolation and speciation of the snowy owl. The extensive centromeric satellite arrays uncovered in this genome highlight centromere evolution as a potentially important driver of genome evolution in owls.

• Hesthagen, Trygve H. & Vøllestad, Leif Asbjørn (2026). Recent human-mediated translocations of non-native and regionally alien freshwater fish species in Norwegian watercourses. Fauna Norvegica. ISSN 1502-4873. 45, p. 21–29. doi: 10.5324/fn.v45i0.6624. Full text in Research Archive Show summary

  We assessed the translocation of freshwater fish in Norway during the period 2013-2021. These introductions include both regionally alien species and non-native species, excluding the pink salmon Oncorhynchus gorbuscha. A network of 12 agencies, organizations and persons was established to obtain information and report on new introductions. Totally, 287 incidents were reported, mainly from lakes. Altogether, this included 21 translocated species, comprising 12 regionally alien species and nine non-native species. The most frequently translocated among the regionally alien species was pike Esox lucius (36 incidents), Eurasian minnow Phoxinus phoxinus (35), rudd Scardinius eryhrophthalmus (31) and roach Rutilus rutilus (14). Non-native species mainly involved carp Cyprinus carpio (38), tench Tinca tinca (28), brook trout Salvelinus fontinalis (20), pumpkinseed Lepomis gibbosus (15) and goldfish Carassius auratus (10). The highest number of introductions were reported from counties in southern and middle parts of Norway. At least 146 incidents, or about 50% of the introductions, have led to the establishment of viable populations. The primary vectors leading to these introductions were intentional release to establish populations for angling (≈ 60%). The species most often introduced for this purpose was pike, tench, brook trout, lake trout Salvelinus namaycush, rainbow trout Oncorhynchus mykiss and carp. Roach and perch Perca fluviatilis may be stocked as forage fish for pike, but probably also other species. Further, introduction of baitfish such as Eurasian minnow and rudd accounted for about 20% of all cases. The extensive unplanned movement of species may disrupt local biodiversity.

• Bergundhaugen, Marie; Sneeggen, Marte & Progida, Cinzia (2026). Nexilin promotes calcium-dependent endo-lysosomal fission required for retrograde transport. Cell Communication and Signaling. 24(1), p. 1–18. doi: 10.1186/s12964-025-02628-8. Full text in Research Archive Show summary

  Late endosomes and lysosomes (LE/Lys) are dynamic organelles primarily involved in the degradation of macromolecules within cells. Beyond this role, they are crucial for nutrient sensing, calcium signalling, cell proliferation and migration. The cytoskeleton is essential for the proper trafficking and function of LE/Lys. However, while the role of microtubules is well-established, the function of the actin cytoskeleton at LE/Lys is less understood. In this work, we performed an siRNA screen to identify actin regulators that play a role at LE/Lys. The screen revealed that the F-actin-binding protein nexilin regulates LE/Lys size as its depletion leads to their enlargement. We show that this is a consequence of inhibited LE/Lys fission and affects the retrograde transport from late endosomes to Golgi. Moreover, our data demonstrate that nexilin interacts with the small GTPase Rab7b and the lysosomal calcium channel TRPML1, and that TRPML1 activation rescues the LE/Lys enlargement caused by nexilin depletion. Taken together, our results indicate that nexilin mediates the interaction between LE/Lys and the acto-myosin cytoskeleton required for the calcium-dependent fission of these organelles.

• Konestabo, Heidi Sjursen; Leinaas, Hans Petter; Gestel, Cornelis A.M. van & Borgå, Katrine (2026). Prior pesticide exposure reduces drought tolerance in Arctic and temperate springtails—Effects of sequential stressors. Environmental Toxicology and Chemistry. ISSN 0730-7268. 45(6), p. 1460–1469. doi: 10.1093/etojnl/vgag046. Full text in Research Archive
• Dierickx, Katrien Alfred C; Kersten, Oliver Sven; Falahati-Anbaran, Mohsen; Sollid, Eirik; Szpak, Paul & Seiler, Martin Thomas [Show all 14 contributors for this article] (2026). The morphology, isotopic ecology, and phylogeny of walrus, Odobenus rosmarus (Pinnipedia: Odobenidae) populations. Zoological Journal of the Linnean Society. ISSN 0024-4082. 207(1). doi: 10.1093/zoolinnean/zlag077. Full text in Research Archive Show summary

  Walruses are classified into nine extant and two extirpated populations across their circumpolar distribution. While there are hints that these differ morphologically, thus far there has been no in-depth comparison of their morphology and ecology, limiting insights into their conservation and evolutionary status. Here, we investigate regional differences in walrus morphology and ecology during the 17th–21st centuries ce by integrating morphometric analysis of crania (N = 188) and mandibles (N = 193), multi-isotope analysis of bone collagen (δ13C, δ15N, and δ34S; N = 142), and genetic analysis (N = 115). The Pacific and Atlantic subspecies show morphological and isotopic distinctions. Distinct regional selection pressures on males and females can be inferred. This was most visible in the extirpated Maritimes walrus, where females had a unique cranium shape. Regional isotopic and genetic differences were also observed; we found regional differences in δ13C, δ15N, and δ34S, and identified multiple genetic clades coinciding with geographic populations. Overall, the comparative insight into the morphological, ecological, and genetic characteristics of different walrus populations sets a frame of reference for conservation management and from which to understand how each has been impacted by human exploitation and environmental changes in the past.

• Tepanosyan, Gevorg; Gevorgyan, Astghik; Poghosyan, Zhenya; Sahakyan, Lilit & Puts, Isolde Callisto (2026). Arsenic and Phosphorus contamination in sediments along the urban river continuum in Yerevan (Armenia). Soil & sediment contamination. ISSN 1532-0383. doi: 10.1080/15320383.2026.2678982. Full text in Research Archive
• Hofmann, Laurie Carol; Bartsch, Inka; Pehlke, Hendrik; Alves-Lima, Cicero; Barreto, Luís M. & Bermejo, Ricardo [Show all 27 contributors for this article] (2026). Assessment of the macroalgal genetic resources maintained in European germplasm banks. Journal of Applied Phycology. ISSN 0921-8971. doi: 10.1007/s10811-026-03882-0. Full text in Research Archive Show summary

  Germplasm banks are important for preserving genetic diversity, yet the availability and long-term maintenance of macroalgal strains in germplasm banks is currently limited in European collections. To support future food security, restoration efforts, and biotechnological innovation, a strategy was recently developed for the long-term preservation of macroalgal genetic diversity. A foundational step in this effort is to assess the existing biodiversity, biogeographical distribution, and commercial relevance of seaweed cultures maintained in European collections. Using a universal data-collection template distributed widely across European seaweed networks, we compiled and analysed information on these seaweed cultures. As of November 2025, the resulting SeaStrains Database of European Seaweed Collections contains 2541 cultures representing 426 species, accounting for only 4% of global and 15% of European macroalgal diversity. The dataset reveals strong taxonomic bias: 74% are brown seaweeds (Ochrophyta), dominated by Laminaria, Saccharina, and Ectocarpus. Saccharina latissima is the most preserved species due to its scientific and commercial importance. Red and green algae are markedly underrepresented (11% and 14%, respectively), likely reflecting cultivation challenges and life-cycle knowledge gaps. Biogeographically, most cultures originate from cold- to warm-temperate zones, with limited representation of the South Atlantic, Indian Ocean, polar and remote regions. Over 60% of cultures are maintained at two institutions: the Culture Collection of Algae and Protozoa (Scotland) and the Alfred Wegener Institute (Germany). This work provides transparent, accessible information on Europe’s macroalgal germplasm resources and represents a crucial step toward a more robust and sustainable European seaweed sector aligned with UN SDG Target 2.5.

• Kokkola, Tuukka; Sipkens, Timothy A.; Paul, Andreas; Shukla, Deeksha; Ihalainen, Mika & Das, Anusmita [Show all 25 contributors for this article] (2026). Highly light-absorbing particle emissions from low-sulfur marine fuels. npj Climate and Atmospheric Science. 9(1). doi: 10.1038/s41612-026-01369-w. Full text in Research Archive
• Pati, Niladri Bhusan; Chung, Brian K.; Holm, Kristian; Sætre, Frank Ove; Reims, Henrik Mikael & Aasebø, Anders Theodor Michaelsen [Show all 12 contributors for this article] (2026). Ultra long-lived plasma cells in the human small intestine produce microbiota-reactive IgA antibodies. Beneficial Microbes. ISSN 1876-2883. p. 1–13. doi: 10.1163/18762891-bja00120. Full text in Research Archive
• Taboada, Sergi; Gracia-Sancha, Carlota; Galià-Camps, Carles; Böhne, Astrid; Monteiro, Rita & Marcussen, Thomas [Show all 18 contributors for this article] (2026). ERGA-BGE reference genome of Xylophaga dorsalis - a common deep-sea wood-boring bivalve with Atlantic-Mediterranean distribution. Open Research Europe. 6. doi: 10.12688/openreseurope.22692.2. Full text in Research Archive Show summary

  Xylophaga dorsalis is a common Atlantic-Mediterranean mollusc that plays a crucial role in deep-sea habitats, where it digests wood that reaches the seabed through a unique symbiosis with specialised bacteria. The reference genome of X. dorsalis thus offers a crucial resource for uncovering the genetic basis of the species adaptability to wood bore in deep-water ecosystems. The entirety of the genome sequence was assembled into 18 contiguous chromosomal pseudomolecules (superscaffolds) and 1 mitochondrial genome. This chromosome-level assembly encompasses 0.451 Gb, composed of 1,259 contigs and 320 scaffolds, with contig and scaffold N50 values of 1.30 Mb and 25.4 Mb, respectively. The genome assembly encodes 19,441 protein-coding genes (34,405 transcripts) and 6,716 non-coding genes.

• Lauretis, Angela De; Santacroce, Marco; Wang, Qiang; Ramirez, Manuel; Ma, Qianli & Lyngstadaas, Ståle Petter [Show all 9 contributors for this article] (2026). Combined Chemical and Mechanical Debridement Enhances Salivary Protein Removal from Titanium while Maintaining Biological Properties. ACS Biomaterials Science and Engineering. doi: 10.1021/acsbiomaterials.5c01973. Full text in Research Archive Show summary

  Effective decontamination of dental implants is essential for managing peri-implant diseases, yet its impact on the salivary pellicle and cell response remains unclear. As the pellicle mediates bacterial and host cell interactions, investigating how decontamination alters its composition is key to understanding the effects on biological outcomes. Accordingly, we examined how a Poloxamer 407 (P407) hydrogel, a P407 + hydrogen peroxide (H2O2) hydrogel, a titanium brush, and their combinations influence the adsorbed salivary proteins and cell adhesion on OsseoSpeed-like titanium surfaces. Surfaces with salivary proteins were treated with different decontamination methods and re-exposed to saliva. Protein quantity was measured using the BCA assay, while the proteomic composition and molecular functions of the adsorbed proteins were determined by liquid chromatography-mass spectrometry and gene ontology analysis. Human bone marrow mesenchymal stem cell (hBMMSC) adhesion was assessed on the surfaces, and cytotoxicity was evaluated using an LDH assay. Protein-coated and protein-free surfaces served as controls. Although protein levels were consistent across groups after either decontamination or recontamination, each treatment produced a different proteomic profile. Mechanical decontamination, alone or combined with chemicals, enhanced protein removal efficiency. Combined treatments yielded reduced protein diversity following recontamination and enriched adhesion-related proteins. None of the treatments compromised hBMMSC adhesion nor made the surface cytotoxic. Decontamination methods selectively modify the proteomic profile. Combined chemical and mechanical decontamination promotes the removal of salivary proteins and limits their readsorption while preserving cytocompatibility, supporting their relevance to peri-implant health.

• Balaguera, Nathalia Chica; Andersen, Aram Nikolai; Munoz, Sara Orellana; Llorente, Ignacio Garcia; P, Aurélie Nguéa & Nakken, Sigve [Show all 14 contributors for this article] (2026). Time-resolved functional genomics using deep learning reveals global hierarchical control of autophagy. Nature Cell Biology. ISSN 1465-7392. 28(3), p. 465–479. doi: 10.1038/s41556-025-01837-0. Full text in Research Archive Show summary

  Recycling of cellular components through autophagy maintains homeostasis in changing nutrient environments. Although its core mechanisms are extensively studied, understanding of its systems-wide dynamic regulation remains limited, particularly regarding how autophagy is inactivated once nutrients are restored. Here we mapped the genetic network that controls activation and inactivation of autophagy during nitrogen changes by combining time-resolved high-content imaging, deep learning and latent feature analysis. This dataset, termed AutoDRY, categorizes 5,919 mutants based on nutrient response kinetics and their contributions to autophagosome formation and clearance. Integrating these profiles with functional and genetic network data uncovered hierarchical and multilayered control of autophagy and revealed multiple new regulatory pathways. Notably, we identified the retrograde pathway as a pivotal time-varying modulator that tunes the expression of core autophagy genes and plays a central role in autophagy inactivation. Together, this study establishes a systems-level resource to guide future investigations of autophagy.

• Assis, Denis Reis de; Pentz, Atle Bråthen; Osete, Jordi Requena; Ievglevskyi, Oleksandr; Vandenberghe, Matthieu & Akkouh, Ibrahim Ahmed [Show all 12 contributors for this article] (2026). Investigating neural impairments in psychotic disorders using electroencephalography and cortical spheroids. Translational Psychiatry. 16(1). doi: 10.1038/s41398-026-03863-4. Full text in Research Archive Show summary

  Synaptic dysfunction is a candidate mechanism in psychotic disorders, yet the precise underlying substrates remain elusive. We investigated how combining in vivo electroencephalography (EEG) and in vitro human cortical spheroid (hCS)-based methods can further our understanding of psychosis pathophysiology during fetal stages of neurodevelopment. Ten individuals with schizophrenia (SZ) or bipolar disorder (BD; 5 males and 5 females) and five controls (CTRL; 3 males and 2 females) underwent EEG assessments, including long-term potentiation (LTP)-like cortical plasticity and mismatch negativity (MMN). hCS were generated from induced pluripotent stem cells of all participants, and immunohistochemistry, Seahorse bioenergetics and patch-clamp recordings were performed. EEG-based LTP-like plasticity was reduced in individuals with SZ and BD. Basal respiration was decreased in BD hCS and VGLUT1 levels were reduced in both SZ and BD hCS. There was a positive association between EEG-based LTP-like plasticity and hCS basal respiration which survived correction. Our data provide further support for roles of mitochondrial and glutamatergic impairments in the synaptic dysfunction of psychosis and demonstrate the potential of combining EEG- and hCS-based methods for early development mechanistic studies of brain disorders.

• Kranjec, Christian; Eilertsen, Ina; Nunes, Luis; Moosavi, Hossein; Berg, Kaja Christine Graue & Eknæs, Mette [Show all 12 contributors for this article] (2026). Common gene mutations in 103 authenticated colorectal cancer cell lines. Oncogenesis. 15. doi: 10.1038/s41389-026-00599-0. Full text in Research Archive Show summary

  Colorectal cancer (CRC) cell lines represent the main molecular subtypes of tumors and are valuable models for preclinical investigations. However, cell lines can diverge over time and careful selection of models based on their molecular features is key. We have authenticated 103 commonly used CRC cell lines and present the mutation profiles of 20 CRC-relevant genes sequenced to an average depth of 575 times coverage. The cell lines reflected the distinct mutation patterns of hypermutation phenotypes associated with microsatellite instability and pathogenic POLE mutations. Hypermutated cell lines appeared to have a stronger mutational divergence and more frequent subclonal mutations, while mutations not associated with hypermutation were more frequently homozygous or hemizygous, classified as pathogenic, and subject to stronger selection pressure. Loss of heterozygosity at mutated loci was primarily observed in tumor suppressor genes. Genetic interactions based on co-occurring mutations identified cell lines representative of particularly aggressive subtypes of CRC, including concurrent BRAF p.V600 and truncating APC mutations, as well as APC/TP53/RAS triple mutations with double hits of APC. This study provides a resource to guide the selection of cell lines for functional studies of CRC, and detailed mutation data including classifications of pathogenicity, variant allele frequencies and illustrations of the mutation distribution along the length of encoded proteins are included.

• Iversen, Lars; Garrastacho, Manuel Ramirez; Hansen, Pernille May; Thiede, Bernd; Thyssen, Jacob Pontoppidan & Rasmussen, Marie Louise Roed [Show all 9 contributors for this article] (2026). Proteomic profiling of tear fluid in patients with atopic keratoconjunctivitis. The ocular surface. ISSN 1542-0124. 41, p. 66–75. doi: 10.1016/j.jtos.2026.05.005. Full text in Research Archive
• Nadeau, Christina; Milkoreit, Manjana; Dischler, Reidar; Kilsti, Sunneva & Hessen, Dag Olav (2026). Climate dissonance: Examining the relationship between climate beliefs and attitudes toward fossil fuel activities in Norway. Energy Research & Social Science. ISSN 2214-6296. 136. doi: 10.1016/j.erss.2026.104750. Full text in Research Archive Show summary

  To meet the goals of the Paris Agreement and limit anthropogenic global warming to 1.5 °C (or below 2 °C), research indicates that a substantial proportion of the world's remaining fossil fuel reserves must remain unextracted. Despite this, several fossil-producing countries continue to expand hydrocarbon activity. Norway represents a particularly important case because it combines high levels of climate concern with continued support for oil and gas production. Given the intrinsic link between climate change and fossil fuel consumption, one might expect heightened concern about climate impacts to translate into greater support among respondents for restricting further hydrocarbon exploration and extraction. This article examines the relationship between climate change beliefs, political affiliation, and support for fossil fuel extraction in Norway. While many studies have examined climate attitudes or fossil fuel policy preferences independently, this paper addresses how these orientations coexist in a fossil-exporting welfare state, the paradox of strong climate concern alongside continued respondent-level support for fossil fuel production. Drawing on nationally representative survey data collected between 2020 and 2024, this study uses descriptive data from multiple years to show the stability of attitudes over time, while regression analyses focus on the 2024 dataset, which contains the full set of relevant variables and provides the most up-to-date snapshot of respondents' views. It further explores how climate attitudes, political orientation, and support for fossil fuel activities intersect to shape attitudes toward supply-side climate policy. Despite relatively high levels of climate scepticism compared to other Western nations, we find that most Norwegians perceive climate change as a serious issue. However, nearly 90% of respondents still support continued oil and gas production. Climate concern is associated with greater support for restricting future exploration, but not with support for ending existing production, and this relationship is strongly patterned by political affiliation. This paradox places Norway in a state of “climate dissonance”, in which concern about climate change coexists with continued endorsement of fossil fuel activities. As a highly educated nation with a strong environmental reputation yet an economy deeply intertwined with fossil fuel wealth, Norway provides a compelling case for understanding why high levels of climate concern do not necessarily translate into support for fossil fuel phase-out in fossil-fuel-dependent democracies.

• Klöcker, Antonia; Arostegui, Martin C.; Ferter, Keno; Bjelland, Otte; Gore, Mauvis A. & Hinriksson, Jan [Show all 14 contributors for this article] (2026). Seasonal residency and large-scale return migration patterns of basking sharks in high-latitude environments of the North Atlantic. Marine Ecology Progress Series. ISSN 0171-8630. 785. doi: 10.3354/meps15153. Full text in Research Archive Show summary

  Marine megafauna adopt diverse movement strategies to balance the costs and benefits of migration amid shifting environments, resources, and reproductive demands. Species with broad latitudinal ranges can exhibit distinct movement patterns at the edges of their distribution. However, pan-latitudinal perspectives on annual movements remain scarce, as exemplified by the planktivorous basking shark Cetorhinus maximus , for which most data derive from temperate waters near the range centre. We satellite-tracked 13 basking sharks tagged near their northern distributional limit in northern Norway for up to 515 d to investigate year-round horizontal and vertical movements. Six of 7 sharks, each tracked for ≥338 d, performed large-scale return movements—departing the Norwegian shelf after summer, occupying the West European Basin and adjacent waters during winter, and returning to the Norwegian Sea the following summer. Individuals covered annual distances averaging ~14000 km, including one transatlantic movement to the southern Sargasso Sea. Vertically, sharks exhibited irregular surface use and isobath tracking in boreal shelf habitats, and mesopelagic occupancy with diel vertical migration in lower-latitude oceanic waters, consistent with known prey distributions. Seasonal movements averaged 30° of latitude, exceeding those of lower-latitude conspecifics, thereby providing first evidence of ‘leapfrog migration’ in basking sharks. These comparably consistent latitudinal movements likely track large seasonal shifts in prey availability within a 2-25°C thermal envelope. As climate change and other anthropogenic pressures alter marine habitats and phenologies, these findings advance understanding of range-edge movement dynamics and underscore the value of long-term, pan-latitudinal studies for assessing population connectivity and guiding dynamic conservation strategies for this endangered megaplanktivore.

• Györkei, Ádám; Johansen, Finn-Eirik & Qiao, Shuo-Wang (2026). Characterization of T-cell receptor loci and expressed repertoire reveals a capacity for robust T-cell response in Atlantic cod (Gadus morhua). Scientific Reports. 16. doi: 10.1038/s41598-026-45018-x. Full text in Research Archive
• Puts, Isolde Callisto; Mostovaya, A.; Henson, H. C.; Allais, L.; Kluijver, A. de & Thyrring, J. [Show all 8 contributors for this article] (2026). Effects of Meltwater on the Arctic Coastal Microbial Food Web: An Experiment With Isotopic Labeling From Young Sound, NE Greenland. Journal of Geophysical Research (JGR): Biogeosciences. ISSN 2169-8953. 131(3). doi: 10.1029/2025JG008921. Full text in Research Archive
• Falnes, Pål & Davydova, Erna (2026). The Protein Histidine Methyltransferase METTL9—From Mechanism to Biological Function. Life. 16(3). doi: 10.3390/life16030445. Full text in Research Archive
• Beneito, Andrea; Balmont, Christian Carrizosa; Alvarez, Oihane; Sarzo, Blanca; Llop, Sabrina & Esplugues, Ana [Show all 13 contributors for this article] (2026). Prenatal exposure to 33 endocrine-disrupting chemicals and pubertal development at age 9 in Spain. Environmental Research. ISSN 0013-9351. 301. doi: 10.1016/j.envres.2026.124527. Full text in Research Archive
• Kaartvedt, Stein (2026). A career studying fjords and oceans in unconventional ways. ICES Journal of Marine Science. ISSN 1054-3139. 83(3), p. 1–11. doi: 10.1093/icesjms/fsag030. Full text in Research Archive
• Thompson, Andrew M.; Dal, Nils-Jørgen; Boldrin, Francesca; Rodriguez, Noelia Alonso; Schäfer, Gabriela & Johann, Kerstin [Show all 14 contributors for this article] (2026). New antitubercular pretomanid analogues as potent payloads in polymeric micelles: Leveraging zebrafish assays to accelerate lead optimisation. European Journal of Medicinal Chemistry. ISSN 0223-5234. 307. doi: 10.1016/j.ejmech.2026.118622. Full text in Research Archive
• Cristofari, Robin; Davis, Leyla R.; Bardon, Gaël; Fernandes, Flávia A. Nitta; Figueroa, Maria Elena & Franzenburg, Sören [Show all 19 contributors for this article] (2026). Lifestyle change accelerates epigenetic ageing in King penguins. Nature Communications. 17. doi: 10.1038/s41467-026-70527-8. Full text in Research Archive Show summary

  A growing body of evidence supports the role of nutrient sensing and metabolism pathways in regulating ageing rate and healthspan, but the diversity of human lifestyles challenges our ability to identify the mechanisms of this age acceleration. Here, we examine how the transition of wild King penguins to zoo husbandry can closely mimic the shift to a Western lifestyle in humans, and shed light on conserved epigenetic changes in responses to sedentary conditions. We show that, just like modern humans, zoo-housed male King penguins experience an extended lifespan, but this comes at the cost of accelerated epigenetic ageing throughout life. This accelerated ageing is associated with differential methylation in key growth and maintenance pathways, including the mTOR and PI3K/Akt networks. Our results demonstrate the conserved link between lifestyle and age acceleration. Such evolutionary evidence may help us to improve risk detection and, ultimately, therapeutics for lifestyle-induced age acceleration in humans.

• Wang, Xinhui; Solhaug, Anita; Garrido, Bruno C.; Mudge, Elizabeth M.; Fon, Mathias & Andersen, Aaron John Christian [Show all 12 contributors for this article] (2026). Structure elucidation of leadbeaterin-1, an ichthyotoxin associated with fish-killing blooms of Chrysochromulina leadbeateri in Northern Norwegian fjords. Harmful Algae. ISSN 1568-9883. 156. doi: 10.1016/j.hal.2026.103104. Full text in Research Archive
• Tjessem, Ingrid Vesterdal; Brysting, Anne Krag; Reitan, Trond; Hjelle, Simen Salomonsen & Eidesen, Pernille Bronken (2026). A shift in species niche through autopolyploidy: From sexual to vegetative reproduction in Saxifraga oppositifolia. Annals of Botany. ISSN 0305-7364. doi: 10.1093/aob/mcag116. Full text in Research Archive Show summary

  Background and Aims Polyploidy has been essential in the evolution of angiosperms, facilitating novel adaptations, enhancing speciation and contributing to the establishment of larger evolutionary lineages. However, newly formed polyploids require sufficient niche differentiation to survive and coexist with the diploid ancestor. Polyploids are commonly reproductively challenged, which may lead to rapid development of asexual reproduction, which may, in turn, lead to reproductive barriers or ecological niche divergence. Through this study, we investigate whether autopolyploidization has induced a shift from sexual reproduction to vegetative propagation in the arctic–alpine Saxifraga oppositifolia (Saxifragaceae) and thus facilitated the establishment of polyploids in mixed-cytotype populations. Methods We sampled data on capsule and seed production, seed germination, rooting ability, and leaf production among cytotypes through a combination of growth chamber experiments and in situ observations in a field set-up across different habitats (ridges, slopes, riverbeds) in Svalbard including >700 georeferenced S. oppositifolia plants with known cytotype (diploid, triploid or tetraploid). Through hypothesis testing and an explorative model search for relevant covariates (e.g. growth form, habitat, soil type), we tested the effect of cytotype on sexual and vegetative reproductive outcomes. Key Results Polyploids had lower sexual reproductive investment (i.e. capsule production and seed production) and higher vegetative investment (i.e. leaf production and rooting ability), showing that polyploidy has significantly affected both sexual reproduction and vegetative propagation. Conclusions Our findings confirm a shift in reproductive strategy towards less sexual investment and enhanced vegetative investment in triploid and tetraploid individuals. This shift may enhance polyploid survival in habitats with shorter growing season and limited pollinator availability, and thus explains their higher frequency in such habitats. These results support autopolyploidy as an evolutionary mechanism that may allow Arctic species to adapt to ongoing, rapid changes.

• Enserink, Jorrit Martijn & Balaguera, Nathalia Chica (2026). AutoDRY: a genome-wide resource revealing phase-specific control of autophagy activation, amplitude, and termination. Autophagy. ISSN 1554-8627. doi: 10.1080/15548627.2026.2660121. Full text in Research Archive
• Nickel, Jana Helene; Laine, Jan Tapio & Foote, Andrew David (2026). Complex Patterns of Hitchhiking Mutation Load Among Stickleback Populations. Genome Biology and Evolution (GBE). 18(4). doi: 10.1093/gbe/evag088. Full text in Research Archive Show summary

  Positive selection causes beneficial alleles to rise to high frequency in a population. This can cause linked genetic variation to “hitchhike,” and thereby also rise in frequency. This linked variation may include deleterious recessive alleles, previously neutrally harbored at low frequency and in heterozygous genotypes. Modeling studies have shown that local effective population size and reduced recombination rate should contribute to the probability of deleterious mutations being swept to high frequency by being linked to beneficial alleles in selective sweeps or selection on inversion karyotypes. Marine sticklebacks have repeatedly adapted to thousands of freshwater habitats that became available after the last ice age, resulting in the formation of distinct marine and freshwater ecotypes. Selection acts on ancient standing genetic variation present in marine populations, causing freshwater-adaptive alleles to increase rapidly over tens of generations. These genomic regions play a key role in the repeated freshwater adaptation of morphological, physiological, and behavioral traits, and evolve under strong selection. Thus, threespine stickleback is an ideal system for investigating the impact of hitchhiking mutation load. We estimate the mutation load in regions of low recombination, including inversions and the Eda haplotype. We find some evidence for increased accumulation of deleterious alleles in one inversion, while this is not the case for two other inversions. Inversions deviated from Hardy–Weinberg equilibrium in several populations due to an excess of homozygotes.

• Moberg, Ingrid Marie; Hansen, Nina; Bergholtz, Helga; Borge, Kaja Sverdrup; Gunnes, Gjermund & Arnet, Ellen Frøysadal [Show all 9 contributors for this article] (2026). Transcriptomic Profiling of Canine Mammary Tumours Reveals Significant Heterogeneity Between and Within Histological Classes. Veterinary and Comparative Oncology. ISSN 1476-5810. doi: 10.1111/vco.70067. Full text in Research Archive
• Krah, Franz Sebastian; Scharmann, Mathias; Weig, Alfons R.; Hess, Jaqueline; Kellner, Harald & Athanasiadis, Antonis [Show all 24 contributors for this article] (2026). Population Genomics of a Rare and a Common Wood–Inhabiting Fungal Species Across Europe. Molecular Ecology. ISSN 0962-1083. 35(3). doi: 10.1111/mec.70260. Full text in Research Archive
• Asplund, Ulrika Jansson; Karlsen, Damian Petkovic; Brysting, Anne Krag; Halvorsen, Rune; Kauserud, Håvard & Kjønaas, Janne [Show all 7 contributors for this article] (2026). Long-term effects of clear-cutting on understory plant communities in boreal forests. Forest Ecology and Management. ISSN 0378-1127. 613. doi: 10.1016/j.foreco.2026.123784. Full text in Research Archive Show summary

  After five centuries of selective cutting in the boreal Fennoscandian forest there was a shift to stand replacing harvest (clear-cutting) in the 1940s. This shift altered light conditions experienced by the forest understory profoundly, from semi-open conditions to light regimes altering between very open in the recently clear-cut forest to very dense some decades later. In this study, we investigated the long-term effects of clear-cutting on vascular plants and bryophytes. Our study system consists of twelve pairs of mesic spruce forests in Southeastern Norway, with a previously clear-cut, but now mature stand and a near-natural forest within each pair. Vascular plant cover was almost twice as high in the near-natural than in the mature, previously clear-cut forest sites, despite similar standing volume and light availability. Overall, previous clear-cutting did not have long-term effects on species richness, but vascular plant species richness was more responsive to soil Ca, a key driver of plant community composition, in the near natural forests. Likewise, the community composition showed a stronger association with soil chemistry in near-natural forests, suggesting that management alters natural drivers of understory communities. The long-lasting effects of clear-cutting was distinct for understory cover and mainly driven by common species such as the keystone species Vaccinium myrtillus, which was substantially less abundant in previously clear-cut stands.

• Klöcker, Antonia; Vihtakari, Mikko Juhani; Arostegui, Martin Christopher; Schlindwein, Axel; Ferter, Keno & Bjelland, Otte [Show all 11 contributors for this article] (2026). Wide-ranging, year-round breaching behaviour of basking sharks revealed by long-term biologging. Biology Letters. ISSN 1744-9561. 22(4). doi: 10.1098/rsbl.2025.0696. Full text in Research Archive Show summary

  Marine megafauna, including various species of cetaceans and fishes, exhibit energetically costly breaching behaviour during which individuals rapidly propel themselves out of the water. The function of breaching remains enigmatic, largely due to short-duration observations of limited spatial extent. Here, we used animal-borne biologgers to record breaching events of plankton-feeding basking sharks (Cetorhinus maximus) over full annual cycles at high temporal resolution (5 s) across broad spatial scales (35° latitude). Recording 577 breaches across four individuals over 366 days (mean 144 yr⁻¹ shark⁻¹), breaching appears to be a routine behaviour in both sexes, peaking in autumn, but occurring across all seasons and habitats, including deep oceanic areas. Notably, we identified thermal constraints on breaching rates in colder water, with a critical minimum observed at 5°C. Beyond demonstrating that breaching is more common than previously recognized, our study suggests it serves several functions, some potentially independent of spatial and temporal contexts (e.g. seasonal courtship), such as ectoparasite removal. The ubiquity of breaching across space and time highlights the need for comprehensive ‘behaviour maps’ for ocean giants to elucidate the physiological constraints, ecological significance and management implications of breaching in a changing ocean.

• Folk, Alexius Werner Thomas; Heino, Mikko Petteri; Ebert, Dieter; Nilsen, Frank; Stenseth, Nils Christian & Mennerat, Adele (2026). Parasites perform poorly at high host densities: an experimental test in the salmon louse Lepeophtheirus salmonis. Proceedings of the Royal Society of London. Biological Sciences. ISSN 0962-8452. 293(2062). doi: 10.1098/rspb.2025.1782. Full text in Research Archive Show summary

  The link between host density and parasite population size is well-established. However, while high host density facilitates parasite transmission, it may negatively impact parasites through more intense competition and/or more intense host immune defence. We assessed the performance of individually tagged female salmon lice (Lepeophtheirus salmonis), an ectoparasite of Atlantic salmon (Salmo salar), under experimental low and high host density conditions, the latter mimicking salmon aquaculture conditions. Lice at high density exhibit greater pre-reproductive mortality, reduced growth, delayed maturation, smaller adult sizes and lower fecundity. Adult size in salmon lice correlates negatively with age at maturity and positively with early fecundity, lifetime fecundity and lifespan. Thus, lice in high-density host populations perform poorly across all life-history traits, probably owing to stronger immune responses of hosts initially exposed to higher parasite doses. This study suggests density-dependent regulation of parasites in intensive agriculture, where hosts are farmed at high densities. Our results further suggest that salmon lice in aquaculture may be selected for greater resistance to host immune defence. As host populations now consist overwhelmingly of farmed fish, continued research is essential to understand the implications for wild salmonids, which are frequently infected by lice originating from farms.

• Ahmad, Zubair; Crisci, Serena; Sun, Bin; Stenseth, Nils Christian & Giannino, Francesco (2026). Can time-dependent optimal interventions reduce Salmonella spread? A multi-pathway ODE model using real data from EU. Computational biology and chemistry. ISSN 1476-9271. 123. doi: 10.1016/j.compbiolchem.2026.108968. Full text in Research Archive
• Kvalheim, Lone; Quaresma, Tânia; Ligeiro, Raphael & Bomfim, Francieli F. (2026). A test of the River Continuum Concept with copepod functional groups in an Amazonian river. Acta Amazonica. ISSN 0044-5967. 56. doi: 10.1590/1809-4392202500873. Full text in Research Archive
• Moges, Amera; Bekele, Afework; Fashing, Peter J.; Yazezew, Dereje; Ibrahim, Hussein & Chane, Meseret [Show all 10 contributors for this article] (2026). Dietary Flexibility of Arsi geladas (Theropithecus gelada arsi) in a Dry, Low-elevation, Human-dominated Landscape at Goro-Jena, Southeast Ethiopia. International Journal of Primatology. ISSN 0164-0291. doi: 10.1007/s10764-026-00547-0. Full text in Research Archive
• Diekert, Florian Klaus; Li, Yuanhao; Nøstbakken, Linda & Richter, Andries Peter (2026). Compliance, environmental regulation, and quota markets. Journal of Environmental Economics and Management. ISSN 0095-0696. 138. doi: 10.1016/j.jeem.2026.103345. Full text in Research Archive Show summary

  Market-based instruments are widely promoted for their efficiency in achieving environmental goals, but their effectiveness depends on enforcement and compliance, which are often imperfect. We develop a theoretical model in which agents face both technological standards and quota regulations, with the possibility of non-compliance with both at the risk of fines. Within this model, we investigate how intrinsic motivation to comply with different regulations affects investment behavior in quota markets. We find that a greater willingness to invest in quotas can result from either a strong intrinsic motivation to comply with quota regulations or a weak motivation to comply with technological standards. To test these predictions, we use survey data and incentivized economic experiments with Norwegian fishers. The empirical results confirm the theory predictions: Fishers who find technological violations less acceptable tend to invest less in quotas, while those who disapprove of quota violations tend to buy more quotas. These findings highlight the critical role of compliance attitudes for quota market behavior and offer insights for designing more efficient environmental

• Ekstrøm, Per Olaf; Nakken, Sigve & Hovig, Eivind (2026). Exploring Taq polymerase induced mutations in part of BRAF exon 15 by sequencing and mutation enrichment. Mutation Research - Fundamental and Molecular Mechanisms of Mutagenesis. ISSN 0027-5107. 832. doi: 10.1016/j.mrfmmm.2026.111934. Full text in Research Archive
• Ni, Yuanming; Bogstad, Bjarte; Ottersen, Geir; Sandø, Anne Britt; Årthun, Marius & Kvamsdal, Sturla Furunes (2026). Predicting Barents Sea Cod Stock Dynamics Using Oceanographic Data and Neural Network Analysis. Fisheries Oceanography. ISSN 1054-6006. 35(5), p. 665–676. doi: 10.1111/fog.70044. Full text in Research Archive Show summary

  Fluctuations in fish populations are driven by recruitment, growth, and mortality—processes heavily influenced by environmental variability, particularly in highly dynamic marine ecosystems such as the Barents Sea. The complex, nonlinear relationships between various environmental drivers and fish stock dynamics remain challenging to capture. Building upon earlier works that predict Barents Sea cod total stock biomass using lagged hydrographic variables, we combine a wide range of updated data and machine learning techniques to improve predictions. Specifically, we employ neural networks, which excel at modeling intricate, nonlinear patterns, using hydrographic variables and fishing mortality as inputs. Our results highlight the potential of machine learning to complement conventional methods, such as linear regression models, in fisheries science, providing more accurate predictions of stock biomass in response to environmental and anthropogenic pressures.

• Eliassen, Lasse Krøger; Garvang, Even Sletteng; Andersen, Tom; Riemann, Lasse & Titelman, Josefin (2026). Metabarcoding and biomass quantification reveal seasonal parasite associations in copepods. Limnology and Oceanography. ISSN 0024-3590. 71(2). doi: 10.1002/lno.70327. Full text in Research Archive Show summary

  Abstract Parasites are important members of ecosystems, and recent metabarcoding efforts have revealed an abundance of microbial eukaryotic parasites in copepods. However, a putative linkage to host community biomass and composition has not been addressed. We performed zooplankton tows monthly for 2 yr at five stations in the Oslofjord, Norway. The samples were cleared of larger, non‐copepod zooplankton and contained mainly copepods and are henceforth referred to as copepod community samples. Metabarcoding was used to detect microbial eukaryotic parasites in the copepod community samples. We also metabarcoded water samples from one of the stations. Copepods were identified and their biomasses were estimated at three of the stations for 1 yr. Calanus spp. dominated biomass in winter, whereas Temora longicornis and other smaller, short‐lived coastal copepods prevailed during summer. Seasonality in the copepod community was less apparent in the deep waters (200 m) where larger, long‐lived copepods abound. The alveolate parasites Hematodinium and Chromidina were detected at most stations throughout the year and occupied a large proportion of the total reads. Although the microbial eukaryotic community in the copepod community samples reflected the seasonal copepod dynamics, common alveolate parasites (e.g., Syndinium , Blastodinium , and apostome ciliates) appeared year‐round. Co‐occurrence analysis suggested several pair‐wise associations between taxa of microbial eukaryotes and copepods. Parasites are a universal component of copepods in this fjord system and seem well‐adapted to seasonal fluctuations in host community composition. We hypothesize that the parasites may have host ranges that incorporate perennial copepods to maintain their presence in seasonally fluctuating environments.

• Fell, Henry Gillies; Bailey, Joseph; Rasoamalala, Fanohinjanaharinirina; Ramasindrazana, Beza; Shipley, Luke & Jones, Matthew [Show all 13 contributors for this article] (2026). Integrating microclimate to understand vector development and disease patterns: challenges and lessons from plague in Madagascar's Central Highlands. Proceedings of the Royal Society of London. Biological Sciences. ISSN 0962-8452. 293(2067). doi: 10.1098/rspb.2025.2496. Full text in Research Archive Show summary

  Plague, the zoonotic vector-borne disease caused by the bacterium Yersinia pestis, shows seasonal infection patterns across the Central Highlands of Madagascar. The disease persists within a complex ecological network involving host and vector species, all influenced by climate. Due to this complexity, links between climate, Y. pestis ecology and human infection remain incomplete. This study developed microclimate-based models to assess climatic impacts on growth cycles of plague vectors Xenopsylla cheopis and Synopsyllus fonquerniei. Using microclimatic modelling, the vector development index (VDI) was calculated to estimate annual developmental phases for each flea species. The uncorrected VDI suggested that development rates were highly variable for X. cheopis compared to S. fonquerniei, which shows greater temporal consistency. Elevated VDI slopes, representing an increased rate of vector development, correlated with plague cases across 61.8–14.7% of areas, implying possible climatic influence on vector-driven disease cycles. However, these associations were not maintained after adjusting modelled temperatures using limited field validation. These findings highlight the complex interactions between climate, vector dynamics and Y. pestis transmission, and emphasize the need for further investigation into burrow microclimates and their seasonal epidemiological roles.

• Eissa, Ahmed; Fredrik Kismul, Jan; Pentz, Atle Bråthen; Elvsåshagen, Torbjørn; Metzner, Christoph & Akkouh, Ibrahim Ahmed [Show all 12 contributors for this article] (2026). Computational Modelling of Novelty Detection in the Mismatch Negativity Protocols and Its Impairments in Schizophrenia. European Journal of Neuroscience. ISSN 0953-816X. 63(6). doi: 10.1111/ejn.70453. Full text in Research Archive
• Lau, Gigi Yik Chee; Gerber, Lucie; Johansen, Anette; Dahl, Helge Andre; Torp, May-Kristin & Bates, Georgina [Show all 11 contributors for this article] (2026). Mitochondrial responses to anoxia-reoxygenation exposure in crucian carp (Carassius carassius). Journal of Experimental Biology. ISSN 0022-0949. 229(4). doi: 10.1242/jeb.251839. Full text in Research Archive
• Cerri, Jacopo; Chirichella, Roberta; Arnold, Walter; Bartoš, Luděk; Borowik, Tomasz & Carranza, Juan [Show all 33 contributors for this article] (2026). Trends of ungulate species in Europe: not all stories are equal. Mammal Research. ISSN 2199-2401. 71(2). doi: 10.1007/s13364-025-00838-6. Full text in Research Archive
• Wood, Ethan; Edvardsen, Bente; Skjånes, Kari & Supraha, Luka (2026). Phycosphere microbiome succession tracks algal growth dynamics during phosphorus-limited wastewater treatment. Algal Research. ISSN 2211-9264. 95. doi: 10.1016/j.algal.2026.104652. Full text in Research Archive Show summary

  Algal-based wastewater treatment (phycoremediation) relies on microbial interactions within the algal phycosphere that are associated with algal growth and nutrient removal. However, the temporal dynamics of these communities under operational conditions remain poorly resolved. Using 16S and 18S rRNA gene metabarcoding, this study characterized bacterial and eukaryotic communities across alga-attached and free-living size fractions and over time in a raceway-based, pilot-scale phycoremediation system using a filamentous algal co-culture under semicontinuous municipal wastewater flow. Bacterial community composition in the phycosphere overlapped substantially with that observed in a previous laboratory-scale study using the same algal co-culture, with many highly abundant ASVs shared across studies, supporting consistency of key community members across scales. Phycosphere community dynamics were temporally aligned with algal growth, with bacterial alpha diversity in the alga-attached fraction highest during periods of active algal growth and declining with the onset of algal phosphorus limitation. During this high-diversity phase, several orders within Alphaproteobacteria were enriched, followed by declines as the algal culture progressed toward reduced growth. Eukaryotic communities also showed clear successional trends, with Perkinsids (Alveolata) increasing during peak algal biomass before giving way to diverse protists and rotifers. These findings demonstrate coordinated temporal patterns between algal growth dynamics and phycosphere microbial succession in pilot-scale wastewater raceways, providing operational insight into microbial community structure under phosphorus-limited phycoremediation.

• Danieli, Krubeal & Lepperød, Mikkel Elle (2026). A bio-inspired minimal model for non-stationary K-armed bandits. Biological cybernetics. ISSN 0340-1200. 120, p. 1–18. doi: 10.1007/s00422-026-01037-5. Full text in Research Archive Show summary

  While reinforcement learning algorithms have made significant progress in solving multi-armed bandit problems, they often lack biological plausibility in architecture and dynamics. Here, we propose a bio-inspired neural model based on interacting populations of rate neurons, drawing inspiration from the orbitofrontal cortex and anterior cingulate cortex. Our model reports robust performance across various stochastic bandit problems, matching the effectiveness of standard algorithms such as Thompson Sampling and UCB. Notably, the model exhibits adaptive behavior: employing greedy strategies in low-uncertainty situations while increasing exploratory behavior as uncertainty rises. Through evolutionary optimization, the model’s hyperparameters converged to values that align with the principles of synaptic mechanisms, particularly in terms of synapse-dependent neural activity and learning rate adaptation. These findings suggest that biologically-inspired computational architectures can achieve competitive performance while providing insights into neural mechanisms of decision-making under uncertainty.

• Kärkkäinen, Virve; Saari, Toni; Rusanen, Minna; Uusitalo, Hannu; Leinonen, Ville & Thiede, Bernd [Show all 9 contributors for this article] (2026). Altered tear fluid protein expression in persons with mild cognitive impairment. Journal of Alzheimer's Disease. ISSN 1387-2877. 110(1), p. 109–119. doi: 10.1177/13872877251413291. Full text in Research Archive
• Giebichenstein, Julia; Warner, Nicholas Alexander; Routti, Heli Anna Irmeli; Harju, Mikael; Varpe, Øystein & Gabrielsen, Geir Wing [Show all 7 contributors for this article] (2026). Accumulation patterns of polychlorinated alkanes in an Arctic marine food web. Environmental Research. ISSN 0013-9351. 299. doi: 10.1016/j.envres.2026.124360. Full text in Research Archive Show summary

  Polychlorinated alkanes (PCAs), otherwise known as chlorinated paraffins, are contaminants of emerging Arctic concern where our understanding of their occurrence and trophic transfer in Arctic food webs remains limited. To investigate biomagnification potential of PCAs, we analyzed short-chain PCAs: C10-C13 and medium-chain PCAs-C14-17 in three Arctic species: polar cod (Boreogadus saida), ringed seal (Pusa hispida), and polar bear (Ursus maritimus) and Subarctic capelin (Mallotus villosus) samples collected from the northern Barents Sea in 2017 and 2021. PCAs-C10-13 concentrations were low, but detectable in all species, while PCAs-C14-17 concentrations were mainly below detection limits in the mammals. PCAs did not biomagnify, as the lowest concentrations were found in polar bear (0.7 ng g−1 lw) and the highest in capelin (56.9 ng g−1 lw). The PCA homologue profiles were similar among Arctic species, with PCAs-C10-13 dominating in polar cod and marine mammals, which may suggest a contribution from long-range atmospheric transport. In contrast, PCAs-C14-17 were most abundant in the Subarctic capelin, likely reflecting a different exposure. Despite differing PCAs-C14-17 concentrations among the two fish species, their PCAs-C14-17 homologue profile was similar, indicating uniform global production trends. Subarctic capelin is increasingly being preyed upon by Arctic predators and may facilitate the biological transport of PCAs-C14-17 into Arctic ecosystems. These findings suggest that climate-driven shifts in species distribution may have the potential to alter contaminant exposure pathways in Arctic marine food webs.

• Schuuring, Sil; Halvorsen, Rune; Eidesen, Pernille Bronken; Niittynen, Pekka; Kemppinen, Julia & Lang, Simone I. (2026). High Arctic vegetation lowers soil temperatures on sunny days despite low stature. Arctic, Antarctic and Alpine research. ISSN 1523-0430. 58(1). doi: 10.1080/15230430.2026.2649436. Full text in Research Archive Show summary

  The impact of vegetation on soil temperatures in low Arctic and boreal regions is well documented,where dense vegetation reduces soil temperatures. However, equivalent empirical evidence forinfluence of sparse, low-stature high Arctic vegetation and its interaction with cloud cover islimited. Improved understanding of this relationship is vital, because soil temperatures driveimportant ecosystem processes, such as nutrient cycling and carbon fluxes. We investigatedwhether effects on soil temperature are found under smaller high Arctic vegetation in Svalbard,Norway, by modeling soil temperatures in relation to vegetation cover and height across forty plots,using July temperature recordings from 2020 to 2023. We found reduced minimum temperaturesunder thicker moss layers and taller forb and shrub vegetation, whereas organic layers reducedmaximum temperatures. These effects were strongest under sunny conditions, whereas shrubcover showed weak interactions with cloud cover. This contrasts with lower latitudes, where shrubsexert strong shading effects and vegetation reduces maximum and raises minimum soil tempera-tures. This discrepancy might stem from smaller diurnal temperature fluctuations, lower vegetationheight, and lower solar radiation in the high Arctic. Our results indicate that predicted vegetationshifts resulting from climate change may lead to complex soil temperature responses in the future.

• Gonzalez, Enrique Blanco; Jorde, Per Erik; Jentoft, Sissel; Robalo, Joana Isabel & Naito, Mana (2026). Selection Against Hybrids Maintains Genetic Divergence Between Populations of a Coastal Cleaner Fish Translocated Across a Genetic Break. Evolutionary Applications. 19(3). doi: 10.1111/eva.70214. Full text in Research Archive Show summary

  Genetic divergence between populations and/or species is mainly driven by reproductive isolation, that is, reduced gene flow, due to either pre- and/or postzygotic barriers. In this study, we investigate the role of (i) reproductive ecological interactions and (ii) mechanisms of evolutionary isolation between two genetically differentiated populations of a coastal fish species, corkwing wrasse Symphodus melops, in a large semi-natural mesocosm basin over a 2-year period. Corkwing wrasse is one of the main cleaner fish species used by the salmon aquaculture industry in Europe, where translocation is a common practice. The parentage analysis performed on the group of offspring survivors at the end of the translocation experiment evidenced strong selective winter mortalities in hybrid offspring (with mixed parental origin). Additionally, it suggested unprecedented assortative mating patterns in corkwing wrasse. Fish of west Norwegian origin experienced stronger intensity of sexual selection and displayed higher relative reproductive success (RRS) than individuals of southern origin under the experimental conditions. Size of the breeder and alternative sneaking behavior in males are two phenotypic traits often selected to attract potential mates and maximize reproductive fitness. However, neither of them had a significant effect on offspring production. Hence, our results suggest that other traits related to mate choice and competition, not examined here, could play a major role. Our results revealed strong selection against hybrids and potential assortative mating between southern and western corkwing wrasses population as two major contemporary drivers reshaping the historical genetic divergence associated to founder events during post-glacial recolonization in Norway. We discuss the relevance of our findings for aquaculture-based fisheries enhancement systems, resource management and conservation.

• Opdal, Anders Martin Frugård; Alix, Maud; Kjesbu, Olav Sigurd; Jørgensen, Christian; Langangen, Øystein Ole Gahr & Karlsen, Ørjan [Show all 11 contributors for this article] (2026). Despite temperature effects on gonad development, timing of spawning is remarkably flexible in Atlantic cod. ICES Journal of Marine Science. ISSN 1054-3139. 83(2), p. 1–12. doi: 10.1093/icesjms/fsag020. Full text in Research Archive Show summary

  At high latitudes, early life stage survival of fish is often associated with how spawning time relates to the timing of the spring bloom. With ocean warming, basic physiological rates of ectotherms, like fish, will speed up—including gonadal development rates, which dictate spawning time. Since warmer water is thought to influence the spring bloom timing differently than that of fish spawning time, the two may fall out of synchrony in the future. The precise mechanisms between temperature and gonadal development and spawning time have, however, been difficult to disentangle. Here, we take advantage of a series of independent laboratory experiments measuring individual oocyte development up to or near spawning for 153 Atlantic cod (Gadus morhua) kept between 3 and 12°C. From these data we derive a predictive, mechanistic equation for daily oocyte growth rate as a function of temperature and oocyte developmental status (diameter). The vitellogenic oocyte growth follows an accelerating pattern, and the model predicts that spawning can advance by up to 7 days per 1°C increase. Within-treatment variation is, however, of comparable magnitude to between-treatment temperature effects. The model was also tested in the field by back-calculating oocyte development of 82 fish (2018–2021) sampled at two locations along the Norwegian coast, using daily ambient temperatures from telemetry tags during vitellogenesis as model input. We find that Atlantic cod are able to initiate vitellogenesis over a period of several months in late summer and autumn, as well as regulate the oocyte development rate across a wide range of temperatures—both leading to significant phenotypic plasticity in spawning phenology.

• Skjæraasen, Jon Egil; Arechavala-Lopez, P.; Karlsen, Ørjan; Olsen, Esben Moland; Meager, Justin James & Nyqvist, Daniel [Show all 12 contributors for this article] (2026). Male Agonistic Behavior on Atlantic Cod Spawning Grounds. Ecology and Evolution. 16(4). doi: 10.1002/ece3.73316. Full text in Research Archive Show summary

  The mating system of the iconic Atlantic cod (Gadus morhua) has been described as a lek, a mating system where male–male agonistic interactions are expected. However, observing such behaviors directly in marine environments is challenging. So far, the evidence supporting the importance of agonistic interactions between males is mainly derived from laboratory studies with fish kept in close confinement, possibly elevating the observed levels and their perceived importance. In natural aquatic systems, agonistic interactions may be inferred from acoustic telemetry transmitters fitted with accelerometers, given that they are associated with high activity levels. A large telemetry dataset on Atlantic cod was collected during (i) a field study at two Western Norway spawning grounds from 2019 to 2024 and (ii) a close confinement net—pen study in 2019–2020. A total of 154 sexed mature Atlantic cod were tagged with acoustic transmitters fitted with accelerometers and depth sensors, yielding ~1.5 million accelerometer detections for subsequent activity analyses. In the net-pens, male cod showed much higher activity levels than females. Overall activity levels were reduced in the field, but male activity levels remained higher than those of females during the spawning period. A prominent feature of coastal cod spawning along the Norwegian coast is that males tend to dwell deeper than females. We therefore explored whether depth influenced activity patterns of males and females. This was indeed the case with males being more active than females at fish depths > 20 m and no sex-difference in activity levels closer to the surface (< 20 m depth). No sex difference in activity levels was found outside the spawning period. Our data suggest that male–male agonistic interactions, inferred from activity levels, are present on natural spawning grounds for Atlantic cod, albeit at reduced levels compared to levels exhibited in net–pen confinement. We hypothesize that the heightened activity levels of males compared to females when occupying deeper waters are related to their overall deeper distribution and territorial and agonistic behavior at these depths, agreeing with the lek description of the cod mating system.

• Dulgheriu, Daniela; Andvik, Clare Margaret; Jourdain, Eve Marie; Borgå, Katrine; Ruus, Anders & Haug, Tore [Show all 9 contributors for this article] (2026). A sensitive liquid chromatography–tandem mass spectrometry analytical method of steroid hormones in small blubber samples from four whale species. Conservation Physiology. 14(1). doi: 10.1093/conphys/coag023. Full text in Research Archive Show summary

  Steroid hormones can give an indication of stress, physiological health and reproductive status in whales; however, analysis is often limited by sample mass. We developed a sensitive analytical method using solid phase extraction–liquid chromatography–electrospray ionization–tandem mass spectrometry (LC–ESI–MS/MS) for the identification and quantification of eight steroid hormones (cortisol, cortisone, testosterone, androstenedione, progesterone, 11-deoxycortisol, 11-deoxycorticosterone and 17-hydroxyprogesterone) in small amounts of whale blubber (≤50 mg). Blubber biopsies were collected from stranded killer whales (Orcinus orca; n = 7), harbour porpoises (Phocoena phocoena; n = 3) and sperm whales (Physeter macrocephalus; n = 4), harvested common minke whales (n = 10; Balaenoptera acutorostrata) and free-living killer whales (n = 2) in Norway and the Barents Sea. Steroid hormones were separated using pentafluorophenyl propyl stationary phase and an optimized gradient programme with a total 20-min run. All samples (n = 26) were analysed at 50-mg sample mass, and a subset (n = 11) at 25 mg or lower. Low limit of detection and limit of quantification values resulted in high detection rates of hormones, and we found similar hormone concentrations between parallel samples and at the lowest tested sample mass (14 mg). Cortisol concentrations in sperm whales (4.3 ± 1.6 ng/g) were four times higher than stranded killer whales (1.1 ± 0.96 ng/g), which in turn were up to four times higher than free-living killer whales (0.23 ± 0.12 ng/g), harbour porpoise (0.64 ± 0.38 ng/g) and harvested minke whales (0.22 ± 0.13), possibly due to fatality type and duration of stress prior to death. We provide the first quantification of blubber steroid hormones in killer whale, minke whale, sperm whale and harbour porpoise, and in less than 50-mg sample mass. By minimizing sample mass without compromising precision or sensitivity, our method allows for steroid hormone analysis even on samples with limited availability, strengthening our ability to monitor and conserve marine mammal populations.

• Kausrud, Kyrre & Stenseth, Nils Christian (2026). Virulence in the Anthropocene: How the evolutionary drivers of disease are changed by human ecological impacts. In Støen, Mariel Cristina; Jakobsen, Jostein & Rutt, Rebecca Leigh (Ed.), One Health, Ecology, and the Politics of Emerging Infectious Diseases. Routledge. ISSN 9781003558217. p. 156–175. doi: 10.4324/9781003558217-10. Full text in Research Archive Show summary

  Humans have been exchanging microbes and viruses with other animal species and our environment throughout our evolutionary history, yet we lack a full understanding of what drives some of these interactions to be virulent, occasionally leading to epidemics or pandemics. Here we give an overview of what we know, suspect, and do not know about the fundamental drivers of disease emergence from a bird’s eye evolutionary perspective, in light of ecology and recent human history. We see that infectious diseases emerge as a property of the interaction between the host, the environment, and the pathogen and that models of disease evolution need to take this interaction into account in the hope of achieving predictive power. That predictive power seems increasingly urgent, as over a century of dramatic progress in the ongoing battle against infectious diseases faces off against biodiversity loss, concentration of the vast majority of mammal biomass into fewer species with less genetic diversity, higher long distance contact rates, increasing environmental variance from climate change, and interactions with pollutants promoting antimicrobial resistance. The already-skewed distribution of health care for those humans working under potentially increasing economic instability would be likely to create increasing risk for emerging diseases, both in humans and livestock. Our current situation is in many ways different from historical precedents in scope and scale, underlining the urgent need to build on current knowledge of how our food chain shapes our diseases – and vice versa.

• Unsgård, Even; Mysterud, Atle; Rivrud, Inger Maren; Hylen, Gro; Øpstad, Samson & Meisingset, Erling (2026). Risk factors for bark stripping damage on Norway spruce by red deer. Wildlife Biology. ISSN 0909-6396. 2026(3). doi: 10.1002/wlb3.01613. Full text in Research Archive Show summary

  Norway spruce Picea abies is an economically important tree species in Europe, actively managed for forestry. Among the most negative biotic factors for growth and hence forest production is damage caused by wildlife, such as damage through bark stripping by red deer Cervus elaphus. We quantified bark stripping damage on Norway spruce trees in across 450 stands (aged 20–72 years) spanning a 400 km latitudinal range along Norway's west coast and analysed the underlying mechanisms driving increased probability of bark stripping by red deer. A total of 74% of tree stands had bark stripping damage. The mean percentage of damaged trees was 16.0%, but 50 stands (11.1% of the stands) had more than 50.0% damaged trees. The most important factor determining probability for bark stripping was broad-scale red deer density, where the probability increased markedly when density reached approximately two harvested red deer per km2. In addition, proximity to agricultural farmland, distance from roads, site productivity, distance between twig whorls and terrain ruggedness index increased the probability of bark stripping. Our study on bark stripping on Norway spruce highlights the importance of red deer population control, but also the importance of evaluating environmental factors as well as site factors and tree characteristics in forestry planning to mitigate damage from red deer.

• Bommerlund, Julie; Ergon, Torbjørn Håkan; Filhol, Simon & Mysterud, Atle (2026). Estimating red deer Cervus elaphus population density using drones in a steep and rugged terrain. Wildlife Biology. ISSN 0909-6396. doi: 10.1002/wlb3.01533. Full text in Research Archive Show summary

  Precise and accurate information about population density, crucial for wildlife management, is difficult to obtain for elusive species living in dense forests or steep and inaccessible terrain. Using unmanned aerial vehicles (UAVs), we developed a method for obtaining absolute population estimates of ungulates living in steep, rugged, and partly forested terrain. The UAVs were used to collect data from four different case study areas in two consecutive months in winter/early spring (before leaf growth) in Lærdal, Norway. The detections of red deer Cervus elaphus from UAV images were done using a double observer protocol, and hierarchal state–space models were fitted to the data using a Bayesian framework to obtain posterior distributions of absolute deer density. Results indicate that availability bias was negligible when deer can be searched for in multiple UAV images of the sites (sample plots) taken from different angles by a UAV at 60 m above ground level but detection probability in the images was significantly below one and must hence be accounted for. Although the credible intervals were rather wide, our results demonstrate that absolute red deer density estimates with quantifiable uncertainties can be produced using this method. Lower credible limits for the estimates indicate that densities in two of the study areas were consistently well above management target densities during the two consecutive months. The high spatial variation in deer densities (at various scales) in our study pose a major challenge, as large areas with a high number of sampling sites must be covered to model the spatial variation and obtain reliable and precise density estimates at a scale relevant for management. We nevertheless conclude that the method has potential for reliable spatiotemporal deer density estimation, given sufficient resources and field efforts.

• Guslund, Naomi Croft; Jonsson, Alexandra; Krabberød, Anders Kristian; Porras, Adrian Lopez; Nørstebø, Simen Foyn & Sørum, Henning [Show all 9 contributors for this article] (2026). IgM-mediated protection drives early B-cell activation and mucosal containment of Vibrio anguillarum in Atlantic cod (Gadus morhua). Frontiers in Immunology. 17. doi: 10.3389/fimmu.2026.1771403. Full text in Research Archive Show summary

  Background: Atlantic cod lack functional MHC class II and CD4, raising fundamental questions about how vaccination generates protection in this species. Methods: We combined single-cell transcriptomic profiling of splenic cells with qRT-PCR across complementary active vaccination and passive serum-transfer experiments to define cellular and transcriptional correlates of immunity to Vibrio anguillarum. Results: Bath-vaccinated fish and recipients of immune serum showed effective containment of infection, with bacterial signals largely restricted to gills and minimal detection in spleen or head kidney, whereas naïve fish frequently developed high systemic bacterial loads by day 3 post-infection. All groups exhibited increased splenic macrophage abundance following challenge, but only naïve fish showed strong and sustained inflammatory activation, consistent with their higher pathogen burden. Vaccinated fish and immune-serum recipients displayed only transient or weak myeloid responses despite similar early neutrophil activation. Across both experimental models, a transcriptionally distinct B-cell subset expanded at the peak of infection. This population showed increased immunoglobulin and MHC class I expression together with innate sensing features, consistent with an activated B-cell state. Although this B-cell subset increased in all groups, the largest expansions were observed in vaccinated fish and immune-serum recipients. Overall, these findings are consistent with antigen-specific IgM enhancing early B-cell activation and contributing to protection against V. anguillarum through coordinated humoral and innate-like B-cell responses. Discussion: These findings identify an antibody-driven mode of immune coordination that operates independently of classical CD4+ T-cell help and provide insight into how effective vaccination can be achieved in vertebrates with divergent adaptive immune architectures.

• Frigstad, Helene; Andersen, Jesper Harbo; Bekkby, Trine; Hammar, Linus; Hemraj, Ashley D. & Hessen, Dag Olav [Show all 13 contributors for this article] (2026). Under pressure: accounting for multiple human pressures outside and inside marine protected areas in the Skagerrak. Frontiers in Marine Science. 13. doi: 10.3389/fmars.2026.1774106. Full text in Research Archive Show summary

  The combined effects of multiple pressures pose critical threats to marine ecosystems. As an initial spatial assessment of cumulative pressures in the Skagerrak, we mapped where multiple pressures coincided with sensitive habitats and species, combining recent spatial data sets on 20 pressures and 39 habitats and species. The spatial data were linked with sensitivity weights obtained with a novel partly data-driven method. We found major spatial variation in the risk of cumulative impacts, identifying areas with high human impact, termed hot spots (such as shallow areas in southern and eastern Skagerrak), and areas with low human impact, termed cold spots (such as the deeper parts of the Norwegian Trench). The dominating human pressures were 1) fishing activities, 2) climate change, 3) underwater noise, 4) input of contaminants, 5) light pollution and 6) input of nutrients. Analyses of human pressures within and outside 20 Marine Protected Areas (MPAs) indicated significantly reduced levels in nine MPAs; however, these reductions were limited (less than 15%). One MPA (Skagens Gren og Skagerrak, DK) had significantly higher total human pressure inside the protected area, while ten MPAs did not yield significant results. We therefore recommend that the conservation measures in MPAs in the region be critically addressed and human pressures mitigated, to reduce the potential negative impact of human activities.

• Duong, Cuong V.; Ta, Le Minh; Pham, Thanh Thuy Thi; Vu, Ngoc Anh & Dinh, van Khuong (2026). Predatory effectiveness of the copepod Mesocyclops thermocyclopoides on Aedes aegypti larvae: insights for biological control. Pest Management Science. ISSN 1526-498X. doi: 10.1002/ps.70776. Full text in Research Archive
• Ronold, Eivind Kverme; Morgado, Luis; Mundra, Sunil; Nybakken, Line; Halvorsen, Rune & Kauserud, Håvard (2026). Above- and belowground communities in boreal forests are tightly linked along common ecological gradients. Plant and Soil. ISSN 0032-079X. doi: 10.1007/s11104-026-08440-8. Full text in Research Archive Show summary

  Aims Fungal communities in boreal forest soils are highly diverse, both taxonomically and functionally, with the majority of fungi associated with living or dead plants as saprotrophs, pathogens or mycorrhizal symbionts. The aim of this study was to examine to what extent soil fungal communities are structured by the above-ground vegetation versus topographic and edaphic factors. Methods We take advantage of a vegetation survey in which plant communities have been monitored in plots located along topographic and edaphic gradients in a boreal forest area in southern Norway, spanning from mesic spruce forests to xeric pine forests. To survey the corresponding fungal communities, we applied DNA metabarcoding of soil samples collected from the same permanent plots. Results The fungal soil communities exhibited a strong structure along the same edaphic and topographic gradients as the vegetation. Plant community composition explained most of the variation in fungal community composition followed by edaphic factors and topography. The xeric pine forest was characterized by high CN ratios, ericoid vegetation, and a correspondingly higher abundance of Ascomycota, many of which form ericoid mycorrhizae or are root-associated. The submesic spruce forest was characterized by higher pH, lower CN ratios, diverse understory vegetation and high abundance of ectomycorrhizal and white-rot litter decomposer Basidiomycota. Conclusions The gradient from mesic spruce- to xeric pine-dominated forest is ubiquitous in boreal forests, and we here show a strong link between composition of vegetation and fungal communities, highlighting long-term effects influencing both plant and fungal communities in similar and predictable ways.

• Nguyen, Xuan Thang; Martiensen, Emily Louise Beecher; Abdelhalim, Mohamed; Tran, Trung; Ledsaak, Marit & Rogne, Marie [Show all 8 contributors for this article] (2026). Proteome-wide multi-omics profiling of osteosarcoma transcription factor networks. bioRxiv (preprint article). doi: 10.64898/2026.03.29.714917. Full text in Research Archive Show summary

  Osteosarcoma (OS) is an aggressive bone cancer that most commonly affects children and young adults. OS exhibits a high degree of genomic complexity, as well as cellular plasticity, and dynamic transcriptional regulation is suggested to contribute to treatment resistance and metastasis. Cell lines are well characterized as models to advance our knowledge on OS biology. HOS and U2OS cells have increased invasiveness and higher migratory ability compared with MG63. In this study, we employed a tandem array of consensus transcription factor response elements (catTFREs) proteomic approach to characterize transcription factor (TF) regulatory networks related to OS aggressiveness. We mapped 7,594 proteins and enriched 352 transcription factors and coregulators. When we integrated proteomics with cell line specific gene expression and chromatin accessibility we classified the proteins into different OS cell line dependent sub-clusters and identified TFs and coregulators common for all cell lines and specific for individual cell lines. We demonstrate that RUNX2, MYBL2 and HMGA2 are specifically enriched in HOS and U2OS and may be linked to the cell aggressiveness. ETV5, JUNB, NFIX and ZEB1 were among TFs specific to MG63. Our analysis provides a more comprehensive understanding of the transcriptional drivers that shape OS regulatory landscapes and may have future therapeutic implications.

• Franke, Björn H.; Schipper, Aafke M.; Avgar, Tal; Börger, Luca; Chatterjee, Nilanjan & Müller, Thomas [Show all 78 contributors for this article] (2026). Local and Landscape‐Level Environmental Conditions Drive Habitat Selection Across Terrestrial Mammal Species. Global Ecology and Biogeography. ISSN 1466-822X. 35(3). doi: 10.1111/geb.70212. Full text in Research Archive Show summary

  Aim Animal movements are a fundamental process affecting communities and ecosystems. Quantifying habitat selection across species and habitats is key for understanding how animals respond to environmental change. Currently, we lack comparative studies that examine how habitat selection varies across species traits and landscapes. We aim to quantify global patterns of habitat selection to help understand the fundamental drivers of movement behaviour. Location: Global. Time Period: Contemporary. Major Taxa Studied: Terrestrial mammals. Methods We estimated selection coefficients for terrain ruggedness, vegetation productivity, human population density and distance to roads of individual terrestrial mammals through step‐selection analysis of 1344 GPS tracks across 48 species. We quantified intra‐ and interspecific variation and tested whether selection coefficients were associated with species traits and habitat availability. Results We observe an overall avoidance of roads and areas of high human population density as well as rugged terrain, with a large proportion of individuals selecting for areas of intermediate NDVI. However, we also found large intraspecific variation in habitat selection and show that this variation is predicted by local and landscape‐level environmental conditions rather than species traits. Individuals in more remote areas exhibited weaker functional responses to human presence than those in more disturbed areas. Avoidance of rugged terrain is also context‐dependent, with stronger avoidance when local ruggedness is high. The only exception to the observed intraspecific variability is consistent species‐level responses to road proximity. Main Conclusions Our findings contribute to the understanding of habitat selection by terrestrial mammals, showing that selection is largely shaped by environmental conditions and that animals exhibit high plasticity in their responses. Our results also provide further evidence for the significant impact of roads on animal movement. These insights can help us to understand the potential effects of environmental change on the behaviour of mammal species around the world.

• Reese, Jan-Ole; Lund, Ingrid Maria Castro; Haugen, Håvard Jostein; Saragliadis, Athanasios; Lyngstadaas, Ståle Petter & Linke, Dirk (2026). A dual-loop chemostat to investigate multi-species biofilms on implant surfaces under adjustable flow conditions. Frontiers in Microbiology. 17. doi: 10.3389/fmicb.2026.1751315. Full text in Research Archive Show summary

  Natural biofilms are typically composed of a mix of different microbial species and are often exposed to strong shear forces resulting from liquid flow. Simple biofilm models that attempt to study biofilms are based on a single species and on static growth conditions. To overcome these limitations, we developed a modular dual-loop reactor that decouples bacterial cultivation from hydrodynamic exposure, enabling independent control of nutrient availability (and thus, cell density) and flow rate (and thus, shear stress). Importantly, the system allows for testing different surface materials in a systematic manner. To validate our setup, we used a community of six keystone members of oral biofilms in conjunction with titanium materials of defined roughness that mimic dental implant surfaces. We found that biofilm mass, robustness, and species distribution not only differ significantly between static and dynamic growth conditions, but also vary strongly with different flow velocities. The biofilms formed under flow could be separated into two fractions, one that washed away very easily, and a more robust, basal layer. At low shear forces, overall biofilm mass was the highest, but at the expense of biofilm robustness. At medium shear forces, the robust fraction of the biofilm had the highest relative content of extracellular matrix. At the highest flow rates, the biofilm mass was low, but late colonizers (represented by the oral pathogens Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans ) had the lowest relative abundance. This is in accordance with the concept that high flow of saliva reduces the risk of oral disease. Future applications of our system will include the systematic testing of antimicrobial coatings or surface design effects under defined flow regimes, opening the path toward better medical implants.

• Calderón-Osorno, Melany; Barrantes-Jiménez, Kenia; Lejzerowicz, Franck Laurent Patrick; Arias-Andres, Maria & Rojas-Jimenez, Keilor (2026). Insights into the riverine metaplasmidome: The role of anthropogenic factors in shaping microbial communities. The Microbe. 10, p. 1–11. doi: 10.1016/j.microb.2025.100640. Full text in Research Archive Show summary

  The environmental plasmidome, encompassing the collective plasmids within an ecosystem, plays a key role in microbial adaptation and evolution. Plasmids, as mobile DNA molecules, enable the transfer of beneficial traits among bacteria, especially in response to environmental stresses. In this study, we developed a novel protocol combining PlasmidSafe DNase and REPLI-g amplification to selectively enrich and characterize plasmidic DNA from polluted environments. We applied this approach to the Virilla River (Costa Rica), a system heavily impacted by urban and industrial activities, analyzing water and sediment samples across seasons and pollution gradients. Our method enabled the recovery of longer, circular contigs confidently identified as plasmids through multiple independent tools, with 28,043 circular sequences primarily linked to Gammaproteobacteria. Contaminated sites, particularly during the rainy season, showed higher plasmid diversity and a marked increase in antibiotic resistance genes (ARGs). This heightened diversity in contaminated environments has implications for the dissemination of antibiotic and metal-resistance genes, as well as other adaptive traits within microbial communities. This research underscores the need to study plasmids in natural environments to better comprehend their ecological roles and potential risks in polluted ecosystems.

• Durant, Joël M.; Langangen, Øystein Ole Gahr; Dolgov, Andrey V.; Lindstrøm, Ulf Ove; Krasnov, Yuri & Nikolaeva, Natalia G. [Show all 7 contributors for this article] (2026). Importance of capelin in the diet of Barents Sea predators relative to alternative prey. Marine Ecology Progress Series. ISSN 0171-8630. 781. doi: 10.3354/meps15078. Full text in Research Archive Show summary

  The Arcto-boreal Barents Sea is significantly impacted by temperature warming, with potential effects on trophic interactions and population dynamics. Capelin, a small pelagic fish species, dominates the Barents Sea’s relatively simple food web. Capelin are an essential link between lower trophic levels and top predators, like in many Arcto-boreal systems. This study investigates the factors controlling capelin consumption by Barents Sea predators. We analysed changes in capelin presence in the diet of predators and related it to capelin and krill abundances, using 8 unique diet data sets from major Barents Sea predators (3 fish, 2 seabird, and 2 marine mammal species) spanning 10-36 yr. Only 2 fish species showed a positive relationship between the percentage of capelin in the stomach and capelin abundance, while all fish species exhibited a negative correlation with krill abundance. This finding suggests that these species replace capelin with krill in their diet based on prey availability. Our results confirm the central role of capelin in the Barents Sea ecosystem, with most predators’ diets being influenced by that species’ abundance. Krill plays a more significant role in the Southern Barents Sea, particularly for central place foragers. Although diet data can have limitations, our study shows that diet analysis remains a valuable method to study predator-prey relationships. This information is essential for understanding predator-prey dynamics of key species in the Barents Sea, supporting ecosystem-based and multi-species fisheries management efforts under current and future climate conditions.

• Bardon, Gaël; Barracho, Téo; Durant, Joël M.; Lecomte, Nicolas; Maho, Yvon Le & Stenseth, Nils Christian [Show all 8 contributors for this article] (2026). Multiannual environmental forcing shapes breeding phenology and success in a sub-Antarctic seabird. Science Advances. 12(11). doi: 10.1126/sciadv.aea6342. Full text in Research Archive Show summary

  Climate-driven phenological mismatches threaten avian reproduction by disrupting food availability during critical breeding stages. In marine ecosystems, time lags between environmental changes and their effects on food webs are challenging to model, yet they can have a profound impact on reproduction at higher trophic levels. We disentangle how oceanic and climatic variability influence the breeding phenology and success of a major predator species in the Southern Ocean, drawing on 24 years of data from 17,000 marked king penguins. We document a 19-day advancement in breeding phenology, alongside increased breeding success (44% in 2000 and 62% in 2023). A sliding-window analysis reveals that sea temperature and primary production in key foraging zones predict both phenology and breeding success, with lags up to several weeks and 2 years, respectively. The amplitude of their recent response, as well as their dependence on multiyear environmental conditions, underscores a potential vulnerability in a context of decreasing environment predictability. However, so far, king penguins appear to be keeping pace with environmental changes and demonstrate a remarkable resilience and important flexibility in the face of variable oceanographic conditions.

• Langangen, Øystein Ole Gahr; Kaartvedt, Stein; Hylland, Ketil & Durant, Joël (2026). The collapse of Atlantic cod in the Oslofjord. Frontiers in Marine Science. 13. doi: 10.3389/fmars.2026.1746235. Full text in Research Archive Show summary

  Coastal fish populations in temperate regions increasingly experience environmental pressures and dramatic decreases in stock size. Currently, there are serious concerns about the status of the Atlantic cod ( Gadus morhua ) in the Oslofjord region, a 120-km inlet in southeastern Norway. Given the recent political debate, the large public interest, and the recent decision to close large areas in the Oslofjord to all fishing, the scarcity of quantitative estimates on cod biomass in the region presents an acute challenge. Typically, the state of the cod in the Oslofjord has been assessed by the analysis of juvenile fish datasets. However, scientific surveys targeting adult life stages are limited, and abundance and biomass estimates are based on relatively short time series and with limited spatial coverage. Here, we demonstrate how commercial landings data can be used to describe a recent decline in catch per unit effort in the region, a proxy related to biomass. These results are highly topical and can serve as a baseline for further investigations on the reasons for the collapse of the cod population. While our results demonstrate the value of the large commercial dataset, the introduction of conservation actions calls for alternative and more comprehensive monitoring in the area for documenting a potential future recovery. Our results highlight research and data needs associated with current efforts to improve the status of fish stocks in general, and the Atlantic cod in the Oslofjord in particular.

• Peri, Marcos Llope; Blenckner, Thorsten; Vasilakopoulos, Paraskevas; McGinty, Niall; Lynam, Christopher P. & Hélaouët, Pierre [Show all 11 contributors for this article] (2026). Stress and resilience in northern European marine ecosystems. Proceedings of the National Academy of Sciences of the United States of America (PNAS). ISSN 0027-8424. 123(8), p. 1–7. doi: 10.1073/pnas.2527939123. Full text in Research Archive Show summary

  Marine ecosystems are facing multiple pressures from human activities, such as fishing and nutrient inputs from farming and agriculture, compounded by the global effects of climate change. As a result, the ecosystem services that societies depend on are at risk from the cumulative impact of these pressures. To better understand how different ecosystems respond, it is essential to assess their resilience. While predicting ecosystem resilience remains challenging, significant progress has been made in developing methods to measure it. In this study, we assessed resilience in four northern European marine ecosystems: the Icelandic Waters, the Barents Sea, the Baltic Sea, and the North Sea, spanning 3 to 5 decades. “Folded stability landscapes” were constructed for the Baltic and North Sea. This region provides a unique setting, with a south-north gradient from temperate to subarctic environments and a southeast-northwest gradient from open to semienclosed topographies. The Icelandic Waters and Barents Sea evolved relatively continuously, while the Baltic Sea and North Sea underwent more drastic changes. By comparing results across these gradients, we explore the role of isolation, level of pressures, and food web complexity in shaping resilience patterns and discuss the implications for managing resilient marine ecosystems in the future.

• Slagsvold, Tore & Husby, Magne (2026). Birds Decorating Their Nests With Plastic May Suffer Less Egg Depredation by Corvids. Ecology and Evolution. 16(1), p. 1–10. doi: 10.1002/ece3.72966. Full text in Research Archive Show summary

  Many birds add anthropogenic material to the nest. This may increase the probability of total failure because the nest may be more easily located by enemies. However, the material may also induce a threat response in predators sceptical to new objects (the Neophobia Hypothesis). We presented artificial nests on the ground each with two quail eggs, in territories of Eurasian mag-pies Pica pica in spring. Some nests were decorated with pieces of white plastic while others were not (control). When nests of both types were presented simultaneously on a magpie territory and only a meter apart, depredation started later for nests with plastic than for control nests, supporting the Neophobia Hypothesis. When a trial was repeated on the same territory later in the season, predation started sooner. However, this was probably caused by habituation to the experimental set up (wildlife camera and artificial nests) and not to the plastic itself because in the repeated trials, the eggs in the nests with plastic were still depredated later than the eggs in the control nests. The nests were not depredated sooner if similar experiments had been conducted on the same territory in the previous year. The onset of depredation was no sooner in territories that initially contained plastic close to the magpie nest than in territories containing no plastic. Finally, when only a single nest was presented on a magpie territory, the time lag until depredation was similar for decorated and control nests, suggesting that the increased detectability caused by decoration outweighed the fear response to the plastic. We conclude that the Neophobia Hypothesis may be relevant to natural cases including birds nesting in habitats containing anthropogenic material and to circumstances with repeated visits by corvids to bird nests, such as in a bird colony.

• Hoff, Siv Nam Khang; Maurstad, Marius Filomeno; Tørresen, Ole K.; Araya, Robin Aasegg; Berg, Paul R. & Præbel, Kim [Show all 8 contributors for this article] (2026). Rapid genome modifications including chromosomal fusions and large-scale inversions are key features in Arctic codfish species. Genome Biology. ISSN 1474-7596. 27. doi: 10.1186/s13059-026-03975-6. Full text in Research Archive Show summary

  Genome evolvability involves activation of transposable elements (TEs) that result in novel genomic rearrangements, including translocations, deletions, duplications, as well as larger structural reorganizations, such as chromosomal inversions and fusions. These genomic modifications contribute to raw genetic variability in which selection can act upon, and thus, promote local adaptation. Results Using a comparative genomics framework combined with the generation of six chromosome-level gadid reference genomes, including the cold-water adapted polar cod ( Boreogadus saida ) and Arctic cod ( Arctogadus glacialis ), we uncover an array of larger and smaller chromosomal reorganizations within this lineage. For the two Arctic codfishes, we detect lineage-specific chromosomal fusions, i.e., five in polar cod vs. eight in Arctic cod, resulting in a reduced number of chromosomes found to be associated with their geographical distribution. For the same species, we identify a high number of partly overlapping chromosomal inversions where a majority (especially within breakpoint regions) display an overrepresentation of specific TE families, accompanied by signatures of high degree of conservation. We further demonstrate involvement of miniature inverted-repeat transposable elements (MITEs) in the expansion of the well-known antifreeze glycoprotein genes in polar cod, and that the three gene clusters were localized in association with chromosomal rearrangements on chromosomes 1, 2, and 14. Conclusions We characterize how the Gadidae lineage has undergone massive genomic modifications — potentially via activation of TEs — throughout their evolutionary history, and particularly for the more Arctic species. These genomic reorganizations have likely played an important role in divergence processes and adaptation to freezing environmental conditions.

• Culp, Joseph M.; Power, Michael John; Christoffersen, Kirsten Seestern; Goedkoop, Willem; Kahilainen, Kimmo Kalevi & Rautio, Milla [Show all 44 contributors for this article] (2026). Freshwater biodiversity in a rapidly changing Arctic: An expert horizon scan of key research questions. Ambio. ISSN 0044-7447. doi: 10.1007/s13280-025-02331-5. Full text in Research Archive Show summary

  Arctic freshwater biodiversity is rapidly changing due to climate warming, resource extraction, infrastructure development, and landscape transformation. To improve understanding, predict future responses, and inform policy formulation, research needs must be clearly identified. Using a horizon scan survey, Arctic freshwater experts from government, international agencies, and Indigenous Peoples identified 77 biodiversity research questions with 17 highlighted as most important for near term assessment. These questions span nine thematic categories: biodiversity and taxonomic challenges, hydrological change, productivity and food webs, ecosystem connectivity, methods, monitoring and assessment, permafrost change, winter ecology, anthropogenic development, and Indigenous Knowledge. Climate change emerged as the major driver among all categories and research questions. A key priority identified was the urgent need for long-term, harmonized monitoring programs among Arctic countries. Multiple knowledge gaps detected suggest that circumpolar research collaborations are required to tackle these issues.

• Goraguer, Lucie Helene Marie; Marquardt, Miriam; Gradinger, Rolf Rudolf; Kohlbach, Doreen; Reigstad, Marit & Assmann, Karen [Show all 17 contributors for this article] (2026). Environmental drivers shaping protist plankton seasonality in the northwestern Barents Sea. Progress in Oceanography. ISSN 0079-6611. 244. doi: 10.1016/j.pocean.2026.103702. Full text in Research Archive Show summary

  Unicellular marine eukaryotes (protists) are important components of the biological carbon pump and form the base of marine food webs, ultimately supporting commercially important fish stocks. However, seasonally resolved data on protist composition, abundance and biomass are rare, especially in high latitude ice-covered oceans. This study presents unique seasonal data on protist community composition and abundance from the northwestern Barents Sea, spanning a latitudinal gradient from open Atlantic waters south of the Polar Front to the seasonally ice-covered Barents Sea shelf and across the shelf break into the Arctic Nansen Basin. Observations were conducted during seven cruises (2018 to 2022) covering periods from early winter to late summer. Protist standing stocks and community composition exhibited pronounced seasonality. Dinoflagellates, particularly Gymnodinium species, dominated the low protist stocks in winter whereas summer communities were more diverse and characterized by dinoflagellates, ciliates and flagellates. Mixo- and heterotrophic feeding modes enable these taxa to persist through the polar night and thrive during the stratified and nutrient-poor conditions in summer. Seasonal differences between dinoflagellates and ciliates likely reflect contrasting feeding and survival strategies. The onset of the phytoplankton spring bloom, dominated by rapidly growing centric diatoms of the genera Thalassiosira and Chaetoceros, occurred in a deeply mixed water column in both open and ice-covered waters. This may have been facilitated by diatoms’ effective defense against protozoan grazers and temporal mismatch between the phytoplankton spring bloom and copepod grazers in Atlantic influenced waters. Our seasonally resolved observations highlight the strong seasonality in both the quantity and quality of protist plankton in the Barents Sea, dynamics which will likely shift with the ongoing decline in sea-ice cover.

• Kandanur, Sai Priya Sarma; Renschler, Fabian A.; Breuer, Lara; Schütz, Monika S. & Leo, Jack Christopher (2026). Mutations affecting the β-sheet at the extracellular opening of the intimin β-barrel domain lead to reduced protein levels and inefficient passenger secretion. Bioscience Reports. ISSN 0144-8463. 46(2). Full text in Research Archive Show summary

  Attaching and effacing pathogens, such as enteropathogenic and enterohaemorrhagic Escherichia coli, rely on an adhesin, intimin, for attachment to enterocytes and downstream effects leading to actin pedestal formation. Intimin belongs to the inverse autotransporter family (type 5e secretion systems), which secrete the extracellular adhesive domain or passenger via a hairpin intermediate. While many of the next steps in secretion are now understood, how the hairpin initially forms is not known. We sought to investigate this by making point mutations at several positions in the β-barrel domain of intimin, as this domain forms at least part of the secretion pore. We made the mutations in a wild-type background and in a stalled intermediate caught in the hairpin conformation, which allowed us to uncouple passenger secretion from hairpin formation. Surprisingly, most of the point mutations did not have an appreciable effect on hairpin formation or passenger secretion, and larger changes such as replacing the entire linker region with a flexible glycine–serine stretch showed only a modest reduction in passenger secretion. By contrast, mutations affecting a small β-sheet at the extracellular face of the intimin β-barrel between two extracellular loops and the C-terminus of the linker had a more pronounced effect on secretion, and abolishing this β-sheet prevented hairpin formation and led to complete loss of the wild-type protein. Our results show that the intimin β-barrel is remarkably tolerant to changes and that the β-sheet on the extracellular side of this domain plays a central role in passenger secretion and protein levels.

• Futter, Martyn; Rankinen, Katri; Audet, Joachim; Wit, Heleen de; Farkas, Csilla & Forsius, Martin [Show all 16 contributors for this article] (2026). Northern Nordic river mouth N: P: Si stoichiometry shows limited evidence of Si depletion. Scientific Reports. 16. doi: https:/www.nature.com/articles/s41598-025-34052-w. Full text in Research Archive Show summary

  River mouth nitrogen: phosphorus: silicon (N:P:Si) stoichiometry can predict marine eutrophication potential. Furthermore, deviations from Redfield molar N: P:Si = 16:1:20 ratios can offer insight into limiting nutrients and risks for harmful algal blooms (HAB). Here, we present N:P:Si stoichiometry based on total P, dissolved inorganic N and dissolved Si for 88 coastal river mouths in Norway, Sweden and Finland between 2017 and 2024. Rivers ranged from ultra-oligotrophic to hyper-eutrophic. N and P concentrations increased from north to south, with no latitudinal Si gradient. Most rivers were either P or jointly NP depleted relative to Si, with no overall evidence of Si depletion. However, there was some evidence of seasonal Si depletion. We show how using multi-element approaches, e.g., the Index of Coastal Eutrophication Potential (ICEP) can help to guide management actions. Specifically, Using Si depletion relative to N and P concentrations as an indicator of HAB potential may offer a means to identify catchments where nutrient load reductions can have the largest benefit on marine ecosystem health. Such multi-element approaches can complement single nutrient assessments based on, e.g., the Carlson Trophic Status Index or Water Framework Directive status class assessments.

• Manzano-Marín, Alejandro; Böhne, Astrid; Monteiro, Rita; Marcussen, Thomas; Struck, Torsten H. & Oomen, Rebekah Alice [Show all 15 contributors for this article] (2026). ERGA-BGE reference genome of Hirudo verbana, a once neglected freshwater haematophagous European medicinal leech. Open Research Europe. 5. doi: 10.12688/openreseurope.21672.2. Full text in Research Archive Show summary

  Hirudo verbana Carena, 1820, commonly known as the southern medicinal leech, is one of several European medicinal leeches, whose full diversity has just recently started to be uncovered. Historically, it has been widely used as a medicinal leech and for centuries it was treated erroneously under the specific name of Hirudo medicinalis L. 1758. Recent molecular and taxonomic analyses have revealed subspecific diversity within the morphospecies H. verbana . Hirudo verbana is a blood-feeding species sucking blood from amphibians, fish, and mammals. It occupies freshwater habitats, typically shallow ponds and lakes. Studies show that this leech species has a "naturally limited microbiome", suggesting it may serve as a powerful model system for the study of gut microbiota. We expect this chromosome-level assembly of H. verbana to serve as a high-quality genomic resource for this most famous leech genus and to serve as a foundation to the study of the diversification and biodiversity of European medicinal leeches, as well as their gut-associated symbionts. The genome of H. verbana was assembled into two haplotypes through a phased assembly approach; however, only the primary haplotype was designated as the reference genome for annotation and downstream analyses. The entirety of the primary haplotype was assembled into 14 contiguous chromosomal pseudomolecules, including the mitogenome. This chromosome-level assembly encompasses 0.18 Gb, composed of 277 contigs and 27 scaffolds, with contig and scaffold N50 values of 1.3 Mb and 13.4 Mb, respectively.

• Lavergne, Sébastien; Rosa, Zoé; Peng, Chuan; Monteiro, Rita; Böhne, Astrid & Marcussen, Thomas [Show all 20 contributors for this article] (2026). ERGA-BGE genome of Androsace saussurei Dentant, Lavergne, F. C. Boucher & S. Ibanez, a recently described plant from the rooftops of Europe. Open Research Europe. 5. doi: 10.12688/openreseurope.21922.1. Full text in Research Archive Show summary

  The reference genome of Androsace saussurei (Ericales: Primulaceae: Primuloideae) provides a valuable resource for understanding the mechanisms of plant adaptations to the highest altitudes where flowering plants can thrive and the speciation mechanisms of plants dwelling on high alpine sky islands. The entirety of the genome sequence was assembled into 20 contiguous chromosomal pseudomolecules. This chromosome-level assembly encompasses 413 Mb, composed of 253 contigs and 101 scaffolds, with contig and scaffold N50 values of 4.95 Mb and 21.2 Mb, respectively.

• Tomasello, Salvatore; Manzo, Eleonora; Monteiro, Rita; Böhne, Astrid; Marcussen, Thomas & Struck, Torsten H [Show all 19 contributors for this article] (2026). ERGA-BGE genome of Xanthium orientale subsp. italicum (Moretti) Greuter. A plant of American origin, now widespread and, in some cases, invasive in Europe. Open Research Europe. 5, p. 367–367. doi: 10.12688/openreseurope.21891.1. Full text in Research Archive Show summary

  The Xanthium orientale subsp. italicum (Asterales: Asteraceae: Asteroideae) reference genome offers a valuable resource for understanding the genetic basis of invasiveness and fitness differences among congeneric species. The entirety of the genome sequence was assembled into 18 contiguous chromosomal pseudomolecules. This chromosome-level assembly encompasses 2.26 Gb, composed of 46 contigs and 32 scaffolds, with contig and scaffold N50 values of 98.8 Mb and 124 Mb, respectively.

• Aguado-Ramsay, Pablo; Lara, Francisco; Draper, Isabel; Conejero, Maria; Böhne, Astrid & Monteiro, Rita [Show all 18 contributors for this article] (2026). ERGA-BGE reference genome of Lewinskya acuminata, a common epiphytic Mediterranean moss with disjunct populations in California and Ethiopia. Open Research Europe. 5. doi: 10.12688/openreseurope.21670.1. Full text in Research Archive Show summary

  The reference genome of Lewinskya acuminata (H. Philib.) F. Lara, Garilleti & Goffinet will enable phylogenomic, biogeographic, and evolutionary studies within the Orthotrichaceae and related bryophyte lineages at a depth previously inaccessible. This species of moss is among the most representative of the Mediterranean epiphytic communities and can be readily identified by its long-acuminate leaves, fusiform capsules with a vestigial exostome, a well-developed endostome of six broad segments, and a dark, puckered peristome mouth when dry. The entirety of the genome sequence was assembled into 6 contiguous chromosomal pseudomolecules, 1 mitochondrial genome, and 2 plastid genomes. This chromosome-level assembly encompasses 0.25 Gb, composed of 51 contigs and 13 scaffolds, with contig and scaffold N50 values of 11.5 Mb and 40.8 Mb, respectively.

• Faria, Rui; Vilela, Rocío Nieto; Lima, Fernando P; Monteiro, Rita; Böhne, Astrid & Marcussen, Thomas [Show all 18 contributors for this article] (2026). ERGA-BGE genome of Patella rustica Linnaeus, 1758: a resource to investigate responses to global warming in the intertidal. Open Research Europe. 5. doi: 10.12688/openreseurope.21608.2. Full text in Research Archive Show summary

  The reference genome of Patella rustica Linnaeus, 1758 will offer a unique opportunity to understand how intertidal organisms respond to the effects of global warming, contributing to improve our predictions about the impact of climate change on the maintenance and diversification of marine biodiversity. A total of 9 contiguous chromosomal pseudomolecules were assembled from the genome sequence. This chromosome-level assembly encompasses 719 Mb, composed of 157 contigs and 24 scaffolds, with contig and scaffold N50 values of 8.52 Mb and 83.6 Mb, respectively.

• Reese, Jan-Ole; Lund, Ingrid M. Castro; Haugen, Håvard Jostein; Saragliadis, Athanasios; Lyngstadaas, Ståle Petter & Linke, Dirk (2026). A dual-loop chemostat to investigate multi-species biofilms on different materials under adjustable flow conditions. Frontiers in Microbiology. 17. Full text in Research Archive Show summary

  Natural biofilms are typically composed of a mix of different microbial species and are often exposed to strong shear forces resulting from liquid flow. Simple biofilm models that attempt to study biofilms are based on a single species and on static growth conditions. To overcome these limitations, we developed a modular dual-loop reactor that decouples bacterial cultivation from hydrodynamic exposure, enabling independent control of nutrient availability (and thus, cell density) and flow rate (and thus, shear stress). Importantly, the system allows for testing different surface materials in a systematic manner. To validate our setup, we used a community of six keystone members of oral biofilms in conjunction with titanium materials of defined roughness that mimic dental implant surfaces. We found that biofilm mass, robustness, and species distribution not only differ significantly between static and dynamic growth conditions, but also vary strongly with different flow velocities. The biofilms formed under flow could be separated into two fractions, one that washed away very easily, and a more robust, basal layer. At low shear forces, overall biofilm mass was the highest, but at the expense of biofilm robustness. At medium shear forces, the robust fraction of the biofilm had the highest relative content of extracellular matrix. At the highest flow rates, the biofilm mass was low, but late colonisers (represented by the oral pathogens Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans) had the lowest relative abundance. This is in accordance with the concept that high flow of saliva reduces the risk of oral disease. Future applications of our system will include the systematic testing of antimicrobial coatings or surface design effects under defined flow regimes, opening the path towards better medical implants.

• Wang, Qiang; Haugen, Håvard Jostein; Linke, Dirk; Lyngstadaas, Ståle Petter & Ma, Qianli (2026). Residuals of Chemical Cleaning Agents Impair Peri-Implant Cell Viability: An in Vitro Study. ACS Biomaterials Science and Engineering. doi: 10.1021/acsbiomaterials.5c01777. Full text in Research Archive Show summary

  Background: Chemical debridement agents are commonly used during the cleaning of implants for peri-implantitis treatment; however, how these agents affect lesion healing remains unclear. In addition, the dose- and time-dependent effects of these residuals on implant biocompatibility remain poorly understood. Materials and methods: We evaluated the effects of active compounds in commercial products-3% hydrogen peroxide (H2O2), 0.43% sodium hypochlorite (NaClO), and 0.12% chlorhexidine with 0.05% cetylpyridinium chloride (CHX-CPC) at graded dilutions on murine osteoblastic cells (MC3T3-E1), human gingival fibroblasts (HGFs), and human bone marrow mesenchymal stromal cells (hBMSCs). Cells were cultured for 24 h, then exposed to the agents for 2, 12, or 24 h. Cytotoxicity and viability were assessed using lactate dehydrogenase (LDH) release and CCK-8 assays, while cell morphology was examined by scanning electron microscopy (SEM). Apoptotic gene expression (BCL2, MCL1, BAX) was analyzed after 2 h using quantitative PCR. Results: At high concentrations, H2O2 and NaClO significantly reduced LDH activity in supernatant, likely due to oxidant-induced enzyme inactivation. All three agents inhibited cell viability in a dose- and time-dependent manner, accompanied by cell shrinkage and deformation. Among the tested cell types, hBMSCs displayed greater resistance to H2O2, maintaining proliferative viability at 0.15% (1:20 dilution). Gene expression analysis revealed that concentrated H2O2 and CHX-CPC downregulated BCL2 and MCL1 expression in MC3T3-E1 cells, with broader suppression of these genes observed in HGFs across all agents. In hBMSCs, high concentrations of the agents did not significantly reduce BCL2 and MCL1 levels. Conclusion: Residual chemical debridement agents, when inadequately removed, compromise the viability of cells in peri-implant tissues in a dose- and time-dependent manner. hBMSCs exhibited greater resistance to apoptosis than MC3T3-E1 cells and HGFs. Thorough removal of residual chemical cleaning agents after peri-implant debridement is therefore crucial to preserve the biocompatibility of the implant and the healing

• Oomen, Rebekah Alice; Cariani, Alessia; Chavarie, Louise; Leone, Agostino; Vella, Adriana & Vella, Noel [Show all 16 contributors for this article] (2026). The genome sequence of Atlantic Bluefin Tuna, Thunnus thynnus (Linnaeus, 1758). Wellcome Open Research. 10. doi: 10.12688/wellcomeopenres.23971.1. Full text in Research Archive Show summary

  We present a genome assembly from a specimen of Thunnus thynnus (Atlantic Bluefin Tuna; Chordata; Actinopteri; Scombriformes; Scombridae). The genome sequence has a total length of 799.05 megabases. Most of the assembly (99.17%) is scaffolded into 24 chromosomal pseudomolecules. The mitochondrial genome has also been assembled, with a length of 16.53 kilobases. Gene annotation of this assembly on Ensembl identified 23,266 protein-coding genes.

• Contardo, Juan; Lillo, Maria Antonieta Labra & Cubillos, Guillermo (2026). Environmental Enrichment Increases Foraging Duration in Chilean Flamingos Under Human Care. Journal of Applied Animal Welfare Science. ISSN 1088-8705. 29(1), p. 144–159. doi: 10.1080/10888705.2025.2524415. Full text in Research Archive
• Nymoen, Ingeborg; Rogge, Frederik Sebastian; Aasen, Anna Hjertvik; Grødem, Sverre; Malthe-Sørenssen, Anders & Lepperød, Mikkel Elle [Show all 9 contributors for this article] (2026). Task and Behavior-Related Variables Are Encoded by the Postrhinal and Medial Entorhinal Cortex During Non-Spatial Associative Learning. eLIFE. 14. doi: 10.7554/elife.106095.1. Full text in Research Archive Show summary

  The medial entorhinal cortex (MEC) is pivotal in spatial computations and episodic memory. In particular, an animal’s position can be decoded from the activity of entorhinal grid cells. However, it remains elusive whether MEC could play a more general role in different types of associative learning and how the representations develop during the learning process. It has been shown that the postrhinal cortex (POR), which is directly connected to MEC, integrates visual stimuli with salient outcomes. Here, we use a non-spatial visual association task to investigate whether MEC neurons represent low-level visual cues during learning. Using a Go/NoGo visual association task, we recorded neural activity in MEC and POR throughout the learning phase as mice associated drifting gratings with rewarded, aversive, or neutral outcomes. Our findings reveal that the neural tuning curves in both the POR and MEC change with the learning of the task. From the start of training, the POR neurons exhibited response tuning to the visual cues, and the tuning was stable to cue orientations during learning. In contrast, MEC neurons did not initially respond very strongly to visual cues but developed a robust tuning toward the rewarded trials. While the MEC’s representation of visual information was limited, it encoded other task elements. A large fraction of the neurons formed distinct functional clusters that were either activated or suppressed by reward-related behavior. Remarkably, these clusters segregated anatomically in MEC and maintained strong within-cluster correlations before and after training. Notably, although the same functional clusters were apparent in the POR, they did not show any anatomical structure as in the MEC. Task reversal induced significant changes in network responses across both regions, with a decrease in overall task-responsive neurons but a slight increase in stimulus representation. Strikingly, information about the choice to lick emerged with learning in both brain areas, and most significantly within the functional cell clusters representing reward consumption and plus-cue stimulus. Our results demonstrate that although neurons in MEC and POR develop behavior-modulated tuning during learning of a non-spatial visual association task, the MEC exhibits stronger within-cluster correlations and anatomical organization. Conversely, the POR population exhibits less structural organization and more specific stimulus-tuning, which is reflective of being a higher visual association area. Our findings reveal that the MEC can encode task– and behavior-related variables beyond spatial information.

• Jamy, Mahwash; Ramond, Pierre; Bass, David; Campo, Javier del; Dunthorn, Micah & Lara, Enrique [Show all 9 contributors for this article] (2026). Towards a trait-based framework for protist ecology and evolution. Trends in Microbiology. ISSN 0966-842X. 34(3), p. 242–251. doi: 10.1016/j.tim.2025.08.008. Full text in Research Archive Show summary

  Protists comprise the vast majority of eukaryotic genetic and functional diversity. While they have traditionally been difficult to study due to their small size and varied phenotypes, environmental sequencing studies have revealed the stunning diversity and abundance of protists in all ecosystems. Protists are key primary and secondary producers across many biomes, with ecological specializations that range from mutualism to parasitism, complex predation behaviors, mixotrophy, detritivory, and saprotrophy. Current genomic and transcriptomic approaches provide valuable insights into protist diversity at the genetic level, but they fall short in capturing the morphological and behavioral traits critical for understanding the functional roles of protists in ecosystems. This knowledge gap hinders our ability to answer important questions about protist functional diversity, including how protist functional groups will respond to environmental change. In this opinion article, we advocate adopting a traits-based approach for studying protist diversity and developing a trait database for protists to support this goal. By integrating examples of recent work characterizing protist functional diversity using a range of approaches, we emphasize the opportunities that trait databases offer and propose strategies for moving towards a trait-based framework to guide future research in protist ecology and evolution.

• Winklhofer, Magdalena; Nilsson, Göran Erik & Lefevre, Sjannie (2026). Long non-coding RNA transcripts in crucian carp brain – annotation and expression patterns in anoxia and reoxygenation. RNA Biology. ISSN 1547-6286. 23(1), p. 1–21. doi: 10.1080/15476286.2026.2643366. Full text in Research Archive Show summary

  Long non-coding RNA transcripts (lncRNAs) are important regulators of various cellular processes, including gene expression. However, whether they are involved in the regulation of anoxia-induced transcriptomic changes in crucian carp ( Carassius carassius ), a species that can survive without oxygen for months at low temperatures, has remained unexplored. The existing genome annotation includes mainly protein-coding genes, which are more straightforward to annotate than the lower-expressed lncRNAs. Therefore, this study aimed to annotate lncRNAs in the crucian carp genome, investigate their potential involvement in regulating mRNA abundance in response to anoxia and reoxygenation, and further characterize any differentially regulated lncRNAs and their potential interaction partners (nearby genes). Using next-generation RNA sequencing of brain samples from crucian carp across normoxia, anoxia, and reoxygenation conditions (n=10 per group), 145,264 transcripts were assembled with a reference-guided approach. Using the bioinformatic tools CPC2, CNCI, CPAT, and FEELnc, we identified 6,072 lncRNAs among the assembled transcripts. We observed a substantial transcriptomic response to anoxia, with a total of 56,440 differentially expressed (DE) transcripts (adjusted p-value < 0.05; | log2(fold change)| > 0.38), including 1,321 lncRNAs. The FEELnc classification module identified multiple proximal RNA transcripts that may help to predict lncRNA functions, and due to their proximity to potential interaction partners (IPs), were likely cis -acting. Most (60%) of the interaction sites between DElncRNAs and their targets were located between genes (intergenic), predominantly on the same strand in intergenic subtypes, and primarily nested in the genic context. The log2-fold changes in RNA abundance of DE predicted IPs exhibited a positive correlation with the log2-fold changes of their corresponding DElncRNAs. These findings indicate that lncRNAs are at least co-expressed with and may regulate transcription of specific genes in crucian carp during anoxia and reoxygenation.

• Hausdorf, Bernhard; Tapia, Elicio; Monteiro, Rita; Böhne, Astrid; Marcussen, Thomas & Struck, Torsten H [Show all 10 contributors for this article] (2026). ERGA-BGE genome of Anisus vorticulus (Troschel, 1834): the Lesser Ramshorn Snail, an endangered freshwater snail protected under the EU's Habitats and Species Directive. Open Research Europe. 5. doi: 10.12688/openreseurope.20499.1. Full text in Research Archive Show summary

  We have generated a high-quality reference genome for Anisus vorticulus to support monitoring of the genetic diversity of populations of this declining freshwater species. The chromosome-level genome assembly encompasses 1.04 Gb, composed of 835 contigs and 77 scaffolds, with contig and scaffold N50 values of 2.35 Mb and 59.2 Mb, respectively. The genome was assembled into 18 chromosomal pseudomolecules.

• Lopes, Ricardo Jorge; Böhne, Astrid; Marcussen, Thomas; Oomen, Rebekah Alice; Struck, Torsten H & Aguilera, Laura [Show all 12 contributors for this article] (2026). ERGA-BGE reference genome of the Azores Bullfinch - Pyrrhula murina Godman, 1866: an IUCN Vulnerable Species endemic to a single island in the Azores Archipelago (Portugal). Open Research Europe. 5, p. 1–16. doi: 10.12688/openreseurope.20666.3. Full text in Research Archive Show summary

  The reference genome of Pyrrhula murina’s reference genome will substantially enhance the current monitoring of genetic diversity and population viability and will allow us to understand the effective population size trends throughout time and recent bottlenecks and population expansions. A total of 42 contiguous chromosomal pseudomolecules were assembled from the genome sequence, using ONT, HI-C and Illumina data. This chromosome-level assembly encompasses 1.2 Gb, composed of 65 contigs and 60 scaffolds, with contig and scaffold N50 values of 65 Mb and 76 Mb, respectively.

• Zhu, Hengyi & Bråte, Jon (2026). Identification and Functional Characterization of microRNAs in Ichthyosporea. F1000 Research. doi: 10.12688/f1000research.162501.1. Full text in Research Archive
• Lauretis, Angela De; Wang, Qiang; Santacroce, Marco; Thiede, Bernd; Ma, Qianli & Lyngstadaas, Ståle Petter [Show all 9 contributors for this article] (2025). A Comparative Study of the Impact of Chemical Debridement Products on the Proteomic Profile of the Salivary Pellicle and Cell Adhesion on OsseoSpeed Titanium Dental Implant Surfaces. ACS Applied Materials & Interfaces. ISSN 1944-8244. 17(39), p. 54592–54592. doi: 10.1021/acsami.5c14570. Full text in Research Archive
• Nguyen, Tan Duc; Nguyen, Van Tai; Dinh, van Khuong; Wiegand, Claudia; Wang, Zhen & Baduel, Christine [Show all 13 contributors for this article] (2025). Multigenerational ecotoxicity of tris(2-butoxyethyl) phosphate to the tropical water flea Ceriodaphnia cornuta and probabilistic ecological risk assessment in freshwater environments. Aquatic Toxicology. ISSN 0166-445X. 283. doi: 10.1016/j.aquatox.2025.107363. Full text in Research Archive
• Abraham, Andrew J.; Hempson, Gareth P.; Roux, Elizabeth le; Maré, Celesté; Taylor, Lyla L. & Webster, Andrea B. [Show all 34 contributors for this article] (2025). Sodium constraints on megaherbivore communities in Africa. Nature Ecology and Evolution. 10(1), p. 105–116. doi: 10.1038/s41559-025-02917-y. Full text in Research Archive
• Nguyen, Tan Duc; Huynh, Trong Nhan; Nguyen, Van Tai; Dinh, van Khuong; Wiegand, Claudia & Pham, Thanh Luu [Show all 11 contributors for this article] (2025). Multigenerational testing reveals delayed chronic toxicity of bisphenol A to Daphnia magna: A common characteristic of endocrine-disrupting chemicals? Environmental Pollution (1987). ISSN 0269-7491. 374. doi: 10.1016/j.envpol.2025.126253. Full text in Research Archive
• Tu, Yanyun; Cheng, Lina; Liu, Xianfeng; Hammerstad, Marta; Shi, Chunlin & Meng, Sida [Show all 9 contributors for this article] (2025). SlIDL6–SlHSL1/2/3 ligand-receptor pairs regulate tomato pedicel abscission. Journal of Integrative Agriculture (JIA). ISSN 2095-3119. 25(1), p. 118–126. doi: 10.1016/j.jia.2025.03.018. Full text in Research Archive Show summary

  Flower and fruit abscission reduce crop yield, so decreasing abscission is a significant agricultural issue. HAESA (HAE) and HAESA-like2 (HSL2) kinases and their ligand, INFLORESCENCE DEFICIENT IN ABSCISSION (IDA) peptide, have been confirmed to be the core elements regulating floral organ abscission in Arabidopsis thaliana. Our earlier research revealed that SlIDL6, a homolog of IDA in tomato, functions similarly to AtIDA, regulating the abscission of tomato flower organs. Here, we further isolated three HAESA-like homologs, SlHSL1/2/3, which are involved in tomato flower abscission. SlHSL1/2/3 are highly expressed in the abscission zone (AZ). The knockout mutant lines of Slhsl1, Slhsl2, and Slhsl3 showed lower flower pedicel abscission than wild type (WT). The double mutant of Slhsl1Slhsl2, Slhsl1Slhsl3, and Slhsl2Slhsl3 further depressed abscission than each of the single mutant lines, while triple mutants Slhsl1Slhsl2Slhsl3 exhibited the lowest abscission, indicating that SlHSL1/2/3 mediated abscission is non-redundancy, at least partially. Treating tomato pedicel explants with SlIDL6 peptide significantly accelerated pedicel abscission in WT. However, it had little effect on the abscission rate of SlHSL1/2/3 knockout lines, indicating that SlHSL1/2/3 are the receptors of SlIDL6 in pedicel abscission. Ethylene action inhibitor 1-methylcyclopropene (1-MCP) can significantly depress the expression of SlHSL1/2/3. Ethylene can significantly accelerate the abscission of WT, while less abscission was found in SlHSL1/2/3 knockout lines. Our findings indicate that SlHSL1/2/3 can act as receptors for SlIDL6 to positively regulate tomato pedicel abscission, and the abscission regulated by SlHSL1/2/3 was partially dependent on ethylene.

• Samaras, Athanasios; Kollias, Spyridon & Pavlidis, Michail (2025). Molecular regulation of chronic stress responses in European sea bass, Dicentrarchus labrax. Frontiers in Endocrinology. 16. doi: 10.3389/fendo.2025.1611667. Full text in Research Archive Show summary

  Introduction: This study examines the effects of predictable repeated chronic stress on the stress response and cortisol metabolism in European sea bass. Methods: Fish were exposed to daily stress for 11 days and sampled the next day before or after an additional stressor. Chronically stressed fish showed an attenuated acute cortisol response and altered circulating cortisone levels. Results and Discussion: Gene expression analyses revealed stress-induced regulatory changes. In the brain, pomc and bdnf mRNA expression was affected by chronic stress, while crf by acute stress. In the head kidney, gr2 was affected by both stress types, whereas gr1 and mr responded only to acute stress. Neither mc2r, encoding the ACTH receptor, nor hsd11b2, responsible for cortisol inactivation, were affected. In the liver, gr2 and hsd11b2 were upregulated under chronic stress, suggesting an adaptive mechanism to regulate cortisol metabolism. In contrast, gill receptor expression remained largely unchanged, except for acute stress-induced gr2, gr1, and mr downregulation in chronically stressed fish, potentially modulating cortisol signaling. These findings suggest that chronic stress alters neuroendocrine regulation, desensitizing the HPI axis and impairing the acute stress response. Understanding these mechanisms provides insights into chronic stress adaptation in fish, with implications for aquaculture and stress physiology research.

• Berezovski, Aleksandr; Hessen, Dag Olav; Børseth, Hanne Halkjelsvik & Andersen, Tom (2025). Optical properties of dissolved organic matter along a salinity gradient from a boreal river estuary to open coastal waters. Marine and Freshwater Research. ISSN 1323-1650. 76(11). doi: 10.1071/mf24244. Full text in Research Archive Show summary

  Context Water darkening is an increasingly relevant problem affecting many coastal ecosystems, and it is exacerbated by human activity and climate change. Aims To determine the spectral, isotopic, and quantitative changes in coloured dissolved organic matter (CDOM) across a salinity gradient from the Glomma River to the outer Oslofjord. Methods CDOM absorbance was measured on a spectrophotometer and organic carbon in the water column was analysed using stable isotopes. Key results Spectral slope and CDOM absorption at 443 nm decreases linearly with an increasing salinity. CDOM absorption exhibited significant variations, with low-salinity samples showing higher light absorption per unit of carbon, but little seasonal variations. δ13C of TOC analysis showed a strong positive correlation with salinity. Conclusion Dissolved organic matter optical characteristics of coastal waters are tightly linked to CDOM. The distance to the river mouth and to the shore are some of the most important factors affecting water clarity. The δ13C of TOC analysis indicated a linear transition from terrestrial to marine carbon sources. Implications The study has shown how coastal darkening can be an important ecological issue mainly in near-coastal areas and describes valuable diagnostic tools for tracking it.

• Putten, E. Ingrid van; Trudeau, Ashley; Mackay, Mary; Obregón, Clara; Post, John R. & Richter, Andries Peter [Show all 8 contributors for this article] (2025). Economic Experiments in Recreational Fishing Studies. In Pope, Kevin L.; Arlinghaus, Robert; Hunt, Len M.; Lynch, Abigail J. & Poorten, Brett T. van (Ed.), Understanding Recreational Fishers. Springer Nature. ISSN 9783031997396. p. 411–442. doi: 10.1007/978-3-031-99739-6_14. Full text in Research Archive Show summary

  Experimentation in natural science is commonplace, and the reasons and methods for undertaking it are well understood. The use of experimental methods has risen remarkably over the last 25 years in the field of economics and has had a tremendous impact on the way economic research is carried out. This raises the question; how can economic experiments advance our understanding of recreational fishing. Here, we argue that many opportunities and benefits exist for the application. There have already been several successful experiments (in the lab or the field) to understand the drivers of recreational fisher behaviour. Despite these efforts, there remains a raft of opportunities to use experiments to help understand cause and effect in terms of recreational fisher behaviour. In this chapter, we provide a taxonomy of economic experiments and highlight their application to recreational fisheries. We sketch how controlled and uncontrolled interventions in recreational fisheries are learning opportunities to better understand fisher behaviour and social-ecological dynamics. Further, we highlight practical aspects of experimentation that will help its implementation and suggest opportunities for future experiments in recreational fisheries.

• Mackay, Mary; Putten, E. Ingrid van; Richter, Andries Peter; Abatayo, Anna Lou; Chuah, Swee-Hoon & Dankel, Dorothy Jane [Show all 8 contributors for this article] (2025). Behavioural Economics for Understanding Recreational Fishers and Fisheries. In Pope, Kevin L.; Arlinghaus, Robert; Hunt, Len M.; Lynch, Abigail J. & Poorten, Brett T. van (Ed.), Understanding Recreational Fishers. Springer Nature. ISSN 9783031997396. p. 261–284. doi: 10.1007/978-3-031-99739-6_9. Full text in Research Archive Show summary

  Fisher behaviour is a key consideration and source of uncertainty for recreational fisheries management. All human behaviour is complex and thus difficult to understand, predict, and manage. In recreational fisheries, classical economic theories of profit maximization or rational choice tend to poorly explain fisher behaviour. Consequently, policy interventions that fail to understand and anticipate behavioural responses of fishers tend to fail their intended objectives. The topic of behavioural economics offers an opening by enriching our understanding of fisher behaviour by studying how psychological mechanisms such as behavioural preferences, beliefs, and cognitive biases affect behaviour. The behavioural economic literature can be leveraged to better understand the impacts of fishery management systems. Identifying behavioural regularities and mechanisms can help to inform and improve the current monitoring, control, and surveillance model of management. Potential applications for novel recreational fisheries management build upon a rich theoretical literature and practice. In this chapter, we introduce behavioural economics and its key theories, describe the types of methods used to study recreational fisher behaviour, explain past applications in recreational fisheries research and management, provide some best practices when applying behavioural economics in research and in the field, and consider future prospects.

• Mendel, Helen C; Hopping, Gene; Undheim, Eivind Andreas Baste; Zuegg, Johannes; Lewis, Richard J & Forbes, Briony E [Show all 8 contributors for this article] (2025). PeptideMiner—neuropeptide discovery across the animal kingdom. GigaScience. 14. doi: 10.1093/gigascience/giaf078. Full text in Research Archive Show summary

  Neuropeptides represent the largest and most diverse class of cell-to-cell signaling molecules, holding important roles in animal physiology and behavior. They are evolutionarily ancient and widely distributed across the animal kingdom. Although over 200 neuropeptides have been identified, only a small fraction has been functionally characterized. A recognized bottleneck is the lack of effective tools to study their biological roles and therapeutic potential. Interestingly, neuropeptide-like peptides are also found in animal venoms, where they contribute to prey capture or defensive strategies. Mapping neuropeptide families across the animal kingdom is challenging due to their high sequence divergence and short mature peptide sequences. To address this, we developed PeptideMiner, a search tool that employs profile-hidden Markov models (profile-HMMs) for family-specific peptide discovery. PeptideMiner was systematically validated and benchmarked against existing methods, demonstrating its superior performance. By applying PeptideMiner to several venom transcriptomes—including 24 previously unpublished datasets—we identified 10 novel natriuretic peptides from distantly related species and 57 novel insulin-like sequences from marine predatory cone snails. Chemical synthesis and structure–activity relationship studies of newly identified conoinsulins at human insulin receptors emphasized the value of our approach in elucidating ligand–receptor interactions and discovering new pharmacological probes and therapeutic leads. PeptideMiner offers a powerful platform for discovering new bioactive peptides and family-specific analogues, accelerating both natural product discovery and evolutionary research.

• Pham, Hung Quoc; Le, Hoang Minh; Phan, Ut Van; Nguyen, Minh Van & Dinh, van Khuong (2025). Seasonal dynamics of plasma estradiol 17β level, gonadosomatic index, and ovarian development in female golden trevally (Gnathanodon speciosus). Scientific Reports. 16. doi: 10.1038/s41598-025-30370-1. Full text in Research Archive Show summary

  Plasma estradiol 17β (E2) and gonadosomatic index (GSI) are reliable biomarkers for assessing gonadal maturity in fish. This study investigated seasonal variations in GSI and plasma E2 concentrations and their correlation with ovarian development stages in female golden trevally (Gnathanodon speciosus), a high-value fish species for marine aquaculture, over an annual reproductive cycle. The broodfish were 900 ± 200 g and 40 ± 5 cm in body weight and total length, respectively. From November to February, plasma E2 levels and GSI remained low, followed by a significant increase from March to October, with E2 peaking during vitellogenesis. Ovarian histology revealed asynchronous oocyte development from March to October, with multiple oocyte stages coexisting, confirming G. speciosus as a multiple-spawning species with a reproductive season spanning March to October. Elevated plasma E2 levels during oocyte growth underscore its pivotal role in driving vitellogenesis. These findings enhance understanding of G. speciosus reproductive physiology, providing valuable insights for optimizing broodstock management, conditioning protocols, and strategic planning for artificial reproduction and seed production for marine aquaculture.

• Berezovski, Aleksandr; Hessen, Dag Olav & Andersen, Tom (2025). Photon budgets and the relative effects of CDOM and pigment absorptions on primary production along a coastal salinity gradient. Frontiers in Photobiology. 2. doi: 10.3389/fphbi.2024.1452747. Full text in Research Archive Show summary

  The study highlights the critical role of CDOM in coastal light attenuation and its impact on primary production (PP). We investigated the spectral attenuation of light due to water, phytoplankton pigments, detritus and coloured dissolved organic matter (CDOM) along a salinity gradient in the outer Oslofjord, Norway. By examining the effects of these components across different seasons, we aimed to elucidate their relative contributions to light absorption and PP. The findings suggest that increased terrestrial CDOM inputs, driven by climate, changed atmospheric deposition and land-use changes, could significantly affect coastal ecosystems by altering light attenuation and consequently PP and potentially leading to other ecological pressures. CDOM consistently dominated light absorption across all stations and seasons, contributing 50%–80% of the total absorption of photosynthetically active radiation. The absorption by CDOM and detritus decreased with increasing salinity, while phytoplankton absorption followed a seasonal succession. PP estimates show high seasonal variability from maximums in June to minimums in November, mainly attributed to, changes in seasonal light availability and phytoplankton biomass, followed by light attenuation by CDOM and differences in quantum yields of photosystem II (PSII). Nutrient analysis showed a seasonal pattern, with the highest nitrogen concentrations in November and depletion during more productive seasons, as well as conservative mixing throughout the salinity gradient. CDOM absorption played substantial, albeit not leading, role in influencing PP estimates, derived from a bio-optical model. CDOM was the main determinant of light attenuation across most wavelegnths.

• Pettersen, Markus Borud; Schøyen, Vemund Sigmundson; Malthe-Sørenssen, Anders & Lepperød, Mikkel Elle (2025). Learning place cells and remapping by decoding the cognitive map. eLIFE. 13. doi: 10.7554/elife.99302. Full text in Research Archive Show summary

  Hippocampal place cells are known for their spatially selective firing and are believed to encode an animal’s location while forming part of a cognitive map of space. These cells exhibit marked tuning curves and rate changes when an animal’s environment is sufficiently manipulated, in a process known as remapping. Place cells are accompanied by many other spatially tuned cells, such as border cells and grid cells, but how these cells interact during navigation and remapping is unknown. In this work, we build a normative place cell model wherein a neural network is tasked with accurate position reconstruction and path integration. Motivated by the notion of a cognitive map, the network’s position is estimated directly from its learned representations. To obtain a position estimate, we propose a non-trainable decoding scheme applied to network output units, inspired by the localized firing patterns of place cells. We find that output units learn place-like spatial representations, while upstream recurrent units become boundary-tuned. When the network is trained to perform the same task in multiple simulated environments, its place-like units learn to remap like biological place cells, displaying global, geometric, and rate remapping. These remapping abilities appear to be supported by rate changes in upstream units. While the model does not learn grid-like units, its place unit centers form clusters organized in a hexagonal lattice in open fields. When we decode the center locations of CA1 place fields in mice, we find preliminary evidence of a similar clustering tendency. This suggests a potential mechanism for the interaction between place cells, border cells, and grid cells. Our model provides a normative framework for learning spatial representations previously reserved for biological place cells, providing new insight into place cell field formation and remapping.

• Nadeem, Nudrat; Nadeem, Muhammad; Bostan, Nazish; Sattar, Sadia; Simm, Roger & Javed, Sundus (2025). Assessment of water quality and occurrence of multidrug-resistant clinically relevant bacteria in drinking water in the twin cities of Pakistan. Environmental Monitoring and Assessment. ISSN 0167-6369. 197(5). doi: 10.1007/s10661-025-13989-5. Full text in Research Archive Show summary

  Water filtration plants are a main source of drinking water for local populations in almost all big cities of Pakistan but these filtration plants are ineffective in eliminating contaminants from water. This study was conducted to evaluate water quality with specific focus on physicochemical parameters and bacterial contamination including occurrence of multidrug-resistant bacteria in drinking water collected from filtration plants ( N = 64) of the twin cities of Pakistan. Physicochemical parameters were analyzed following American Public Health Association standard guidelines and total coliform count was determined using membrane filtration method. Gram-negative bacteria were isolated and characterized in terms of species and antibiotic susceptibility. Elevated levels of total dissolved solids, nitrates, total coliforms, lead and copper were found in several samples. Multivariate correlation coefficient revealed significant positive correlation between nitrate levels and total coliform count in bacteriologically contaminated samples. Antibiotic resistance patterns revealed multidrug-resistant and extensively drug-resistant bacteria with high resistance against third generation cephalosporins. Our results highlight the urgent need for improved water filtration processes and regular monitoring to provide safe drinking water to the local community.

• Stein, Johannes; Ericsson, Maria; Nofal, Michel; Magni, Lorenzo; Aufmkolk, Sarah & McMillan, Ryan B. [Show all 16 contributors for this article] (2025). Cryosectioning-enhanced super-resolution microscopy for single-protein imaging across cells and tissues. Proceedings of the National Academy of Sciences of the United States of America (PNAS). ISSN 0027-8424. 122(32). doi: 10.1073/pnas.2504578122. Full text in Research Archive Show summary

  DNA-points accumulation for imaging in nanoscale topography (DNA-PAINT) enables nanoscale imaging with virtually unlimited multiplexing and molecular counting. Here, we address challenges, such as variable imaging performance and target accessibility, that can limit its broader applicability. Specifically, we enhance its capacity for robust single-protein imaging and molecular counting by optimizing the integration of total internal reflection fluorescence microscopy with physical sectioning, in particular, Tokuyasu cryosectioning. Our method, tomographic and kinetically enhanced DNA-PAINT (tkPAINT), achieves 3 nm localization precision across diverse samples, enhanced imager binding, and improved cellular integrity. tkPAINT can facilitate molecular counting with DNA-PAINT inside the nucleus, as demonstrated through its quantification of the in situ abundance of RNA Polymerase II in both HeLa cells as well as mouse tissues. Anticipating that tkPAINT could become a versatile tool for the exploration of biomolecular organization and interactions across cells and tissues, we also demonstrate its capacity to support multiplexing, multimodal targeting of proteins and nucleic acids, and three-dimensional (3D) imaging.

• Buhhalko, Natalja; Kuddithamby, Gunaalan; Vianello, Alvise; Rotander, Anna; Vidal-Liñán, Leticia & Beiras, Ricardo [Show all 19 contributors for this article] (2025). Microplastics (10 µm-5 mm) in European Atlantic Coastal Waters. Environmental Advances. 21, p. 14–14. doi: 10.1016/j.envadv.2025.100644. Full text in Research Archive Show summary

  Microplastics (MPs) are pervasive pollutants in coastal waters, raising significant ecological concerns. This study assessed the abundance and characteristics of small-sized MPs (down to 10 µm) across European Atlantic coastal sites using harmonized sampling and analytical methods. A filter-pump microplastic sampler, the "Universal Filtering Object" (UFO), was employed at all sites, with Manta net (300-µm mesh) sampling conducted at selected locations. Microplastic concentrations ranged from <10 MPs m-3 to >1600 MPs m-3, with the Gulf of Finland showing the lowest concentration (5 MPs m-3) and the Scheldt estuary in Belgium the highest (1603 MPs m-3). Most MPs (80%) were <300 µm, primarily consisting of polyester, polypropylene, and polyethylene fragments. Manta net sampling consistently underestimated both total microplastic concentrations and microplastics larger than 300 µm compared to UFO sampling. Estuaries and wastewater effluents were identified as pollution hotspots, strongly influencing local MP distributions. The median microplastic concentration found in European Atlantic waters in this study was lower than the global median for coastal waters measured using pump-based sampling devices. Although current MP levels are unlikely to pose an immediate risk to the marine pelagic food web, the projected increase in plastic production, combined with its low degradability and chemical leaching, underscores the urgency of implementing mitigation measures to prevent future environmental impacts.

• Tabane, F; Cazier, F; Dewaélé, D; Hylland, Ketil; Ba, CT & Fall, M (2025). Evaluating the histopathology, condition index and stress-on-stress response of caged brown mussels Perna perna for monitoring marine coastal pollution in Senegal. African Journal of Marine Science. ISSN 1814-232X. 47(2), p. 129–141. doi: 10.2989/1814232x.2025.2485075. Full text in Research Archive Show summary

  This study is the first in a coastal West African country to evaluate the histopathology, condition index and stress-on-stress response time of caged brown mussels Perna perna for use in pollution monitoring of coastal ecosystems. Perna perna collected from an unpolluted area on the coast of Senegal were divided and transplanted to a polluted site or maintained at the reference site for an exposure–depuration experiment. After 4 weeks of exposure, the mussels deployed at the polluted site (Port of Dakar) were then transferred to the cleaner reference site (Pointe des Almadies) for depuration. Mussels exposed to the polluted waters of the seaport had bioaccumulated polycyclic aromatic hydrocarbons (PAHs) as well as lead, copper and selenium; furthermore, changes were observed in their digestive gland histology, and their stress-on-stress response measured as median survival time (LT50) had decreased. By the end of the 4-week depuration period at the reference site the mussels showed signs of recovery, specifically in terms of their digestive tubule architecture and tolerance to air exposure. The results demonstrate that caged P. perna could be used as bioindicators for monitoring coastal environmental pollution in West Africa.

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• Pienkowski, Anna; Schalamon, Florina Roana; Dahl, Tina; Eidesen, Pernille Bronken; Furze, Mark F.A. & Hartkop, Matthew [Show all 11 contributors for this article] (2026). Teaching Manual for Field Assistants. Universitetssenteret på Svalbard. 41 p. Full text in Research Archive Show summary

  Conducting educational fieldwork in the natural sciences is often a demanding task, particularly in the Arctic; for many students it is also a new experience. However, fieldwork has a high potential to add great value to conventional classroom lectures and lab work. Alongside the course responsible and students in the field, typically one or several teaching assistants (TAs) are involved in a given course. An important task for these assistants is to contribute towards the best possible learning environment for the students through a range of practical and theoretical tasks. However, they seldom receive formal training in their tasks, and much is learned simply by doing and or by informal knowledge transfer from, for example, more senior students and the course responsible. This shortcoming was addressed by a 3-day course held for the first time at UNIS (University Centre in Svalbard) during spring 2021 and subsequently in 2022. In 2024 and 2025 the course was extended to 5 days. The course, titled ‘The UNIS Field TA Academy’, covers the following topics: introduction to pedagogical theory and teaching; feedback and feedback culture; group work; conflict resolution; diversity, equity, and inclusion; and field learning. This manual is a summary of the course topics and is expanded based on feedback from former field TAs, students, and course responsibles.

• Croft, Darren P.; Foote, Andrew David; Garland, Ellen C. & King, Stephanie L. (2026). The Evolution of Cetacean Societies. University of Chicago Press. ISBN 9780226840574. 436 p. doi: https:/press.uchicago.edu/ucp/books/book/chicago/E/bo257312594.html. Full text in Research Archive Show summary

  Cetaceans—whales, dolphins, and porpoises—represent an evolutionary peak with respect to their advanced cognitive capacities; flexible communication systems; and structured, multilevel societies. Indeed, the social lives of whales and dolphins have long fascinated scientists and the public alike. The Evolution of Cetacean Societies provides a comprehensive overview of the significant advancements made in studying cetacean behavior and ecology over the last twenty-five years, focusing on our growing understanding of these animals’ complex social lives. Bringing together scientists from multiple disciplines, the volume summarizes key innovations and progress related to studying cetacean societies’ cultural and genetic basis, their complex social structures, their use of cooperation and patterns of social conflict, and their significant interactions with humans. Each chapter provides an in-depth account of the social lives of whales and dolphins, incorporating the latest cutting-edge research from genomics, communication, network analysis, and animal culture to explain how these animals form societies, maintain relationships, and share information. The final chapters focus on the existential threats facing these diverse and charismatic species, how human-cetacean interactions have shaped our perceptions, and what scientists can learn from their diverse social lives by championing researcher diversity in marine mammal science. The result is an essential and forward-looking book that both contextualizes the lessons of the past two decades and questions the challenges these enigmatic species might face in the future.

• Ottersen, Geir; Blenckner, Thorsten; Hátún, Hjálmar; Maar, Marie; Niiranen, Susa & Schourup-Kristensen, Vibe [Show all 7 contributors for this article] (2025). Nordic Marine Ecosystems in a Changing Climate. Nordic Council of Ministers. ISBN 9789289382489. 98 p. doi: 10.6027/temanord2025-541. Full text in Research Archive Show summary

  The aim of the NorMECC project and this report is to make available a good overview of the already observed and expected future responses to climate change of a wide range of marine species in the Nordic waters of the Baltic Sea, the North Sea, the Norwegian and Icelandic Seas, the seas around Greenland, and the Barents Sea. The report reviews and assesses scientific articles and other knowledge sources, including papers published up until February 2025. In addition to this literature review, we also provide a short synopsis of the input from a small, targeted group of Nordic managers and decision makers who were challenged to describe which climate change related pressures they consider to be the largest treats to our marine ecosystems.

• Ryvarden, Leif (2025). Synopsis Fungorum 53: Cyphelloid fungi in Scandinavia – a preliminary synopsis. Fungiflora. ISBN 9788290724752. 18 p. Full text in Research Archive
• Ryvarden, Leif (2025). Synopsis Fungorum 51: POROID GENERA - A WORLD SYNOPSIS. Fungiflora. ISBN 9788290724738. 72 p. Full text in Research Archive

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• Gundersen, Sveinung & Bianchini, Federico (2026). D3.4 (M48) - Report on developments and operations of the FAIRtracks ecosystem (an ELIXIR Norway ELIXIR3 deliverable). doi: 10.5281/ZENODO.23341212. Full text in Research Archive
• Munoz, Sara Orellana; Haberkorn, Chloé; Csoboz, Balint; Stelkens, Rike & Peris, David (2026). Mitochondrial–nuclear interactions shape hybrid physiology in Saccharomyces. Full text in Research Archive
• Sorribes-Daudén, Raquel; Vanacloig-Pedrós, Elena; Aguilar-Díaz, Alejandro; Martínez-Pastor, María Teresa; Peris, David & Puig, Sergi (2026). Unravelling adaptive mechanisms of copper tolerance in yeasts of enological interest. Full text in Research Archive
• Araque, Luis; Schweizer, Gabriel; Morard, Miguel; Aguilar-Díaz, Alejandro; Pérez-Adrián, Ana María & Bonet-Aparici, María [Show all 13 contributors for this article] (2026). Defining species boundaries in eukaryotic microorganisms: a persistent puzzle. Full text in Research Archive
• Schweizer, Gabriel; Morard, Miguel; Araque, Luis; Aguilar-Díaz, Alejandro; Pérez-Adrián, Ana María & García-Ríos, Estéfani [Show all 7 contributors for this article] (2026). Can we define microbial species? Insights from the Saccharomyces genus. Full text in Research Archive
• Sjøberg, Mari Heum; Bjerknes, Anne-Line; Burner, Tony; Enqvist-Jensen, Cecilie; Lange, Thomas de & Sandberg, Magnus Henrik [Show all 12 contributors for this article] (2026). Forskning og følelser - NRK. Full text in Research Archive Show summary

  Det er flott at kjendiser engasjerer seg. Men de kan ikke erstatte fagkunnskap.

• Stensrud, Eivind; Hyvärinen, Olli Petteri; Rostum, Tarjei; Angell, Thorvald; Knutsen, Halvor & Lundström, Karl [Show all 8 contributors for this article] (2026). PREDATORS AS SENTINELS: UNRAVELING TROPHIC SHIFTS IN A DARKENING FJORD USING dDNA AND STABLE ISOTOPES OVER THE LAST 20 YEARS. Full text in Research Archive Show summary

  The Greater Oslofjord, like many other coastal systems, is undergoing rapid ecological shifts driven by climate change, coastal freshening and darkening. To understand how these bottom-up stressors restructure food webs, we utilized a multi-trophic approach analyzing three sympatric predators (approx. 500 individuals): Harbour seals (Phoca vitulina), Great Cormorants (Phalacrocorax carbo), and Atlantic Cod (Gadus morhua). We combined dietary DNA (dDNA) metabarcoding with stable isotope analysis (δ13C, δ15N) to trace temporal and spatial dietary changes over 20 years. Traditional morphological methods often fail to capture soft-bodied prey and secondary consumption; thus, we used dDNA combined with novel reference databases to maximize taxonomic resolution. Our dDNA results revealed high-resolution predation data, including the detection of secondary consumption (zoo- and phytoplankton) alongside primary prey, effectively mapping the food web from top predators down to primary producers. Isotope data complemented this by delineating trophic niche widths and source of primary production (land vs. sea). We observed distinct dietary variations linking predator foraging behavior to environmental gradients. This included observable changes over the last 20 years, such as an increase in invasive species in their diet and a shift in zoo- and phytoplankton composition. These findings demonstrate that combining molecular and isotopic analysis of top predators provides a powerful tool for monitoring the cascading effects of anthropogenic changes on marine food webs.

• Carlsen, Eira Catharine Lødrup; Pismeniuk, Anfisa; Wei, Jing; Ippach, Mats Rouven; Dörsch, Peter & Westermann, Sebastian [Show all 9 contributors for this article] (2026). FROM PEAT TO PONDS: LANDSCAPE HETEROGENEITY DRIVES METABOLIC NETWORKS AND GREENHOUSE GAS RELEASE FROM THAWING PERMAFROST. Full text in Research Archive Show summary

  As permafrost landscapes degrade, they transform into a hydrological mosaic of dry palsas, collapsing thermokarst slumps, and water-saturated ponds. This physical reorganization creates steep gradients in redox potential and organic matter quality, fundamentally altering the thermodynamic constraints on microbial metabolism. We investigated greenhouse gas (CO2, CH4, N2O) production potentials across several permafrost thaw gradients in sub-Arctic peatlands of Northern Norway, linking landscape-scale changes to genome-resolved metabolic networks. By integrating high-resolution metagenomics with organic matter and greenhouse gas production characterization, we found that thaw features act as distinct thermodynamic bioreactors. In water-saturated, anoxic peat layers, oxygen limitation selects for "slow" metabolic guilds specialized in fermentation and methanogenesis while other oxygenated features are constrained by the quality of organic matter—specifically the accumulation of polyphenols and aromatic compounds acts as a metabolic "latch". We show that the shift from oxic to anoxic conditions triggers a non-linear restructuring of the microbial network, where less efficient central metabolism drives high N2O and CH4 yields but suppressed CO2 production. These findings demonstrate that predicting the permafrost-carbon feedback requires mapping the "metabolic landscape"—where organic matter quality and redox thresholds ultimately tune the greenhouse gas release from thawing landscapes to the atmosphere.

• Riis-Pedersen, Christine; Carlsen, Eira Catharine Lødrup; Lejzerowicz, Franck Laurent Patrick; Hessen, Dag Olav & Eiler, Alexander (2026). HOW OPTICS AND THERMODYNAMICS SHAPE METHANE EMISSIONS FROM LAKES. Full text in Research Archive Show summary

  The interactions of light regime and physical stratification can be argued to dictate greenhouse gas flux through determining the thermodynamics in lake systems. Using geochemical profiling and metagenomics, we reconstructed metabolic networks in a wide range of lakes including ferruginous (iron-rich) and euxinic (sulfide-rich) systems. We observed significant methane accumulation in the anoxic monimolimnion—up to 420 µM in ferruginous lakes—yet surface levels remained low, indicating a highly efficient biofilter at the chemoclines. We identified a tight thermodynamic coupling between phototrophs and methanotrophs driven by oxidant regeneration. In ferruginous lakes, anoxygenic phototrophs likely use reduced iron (Fe2+) as an electron donor. This process regenerates oxidized iron (Fe3+), while in euxinic light energy is utilized to recycle essential electron acceptors such as SO42- (e.g., Chlorobium), required for anaerobic methane oxidation. Oxygenic phototrophs (e.g., Cyanobium) detected at and above the chemocline likely provide oxygen. This supply sustains aerobic methanotrophs like Crenothrix and Methylobacter even in suboxic waters. Hence methanotrophic capacity is ultimately constrained by optical properties selecting for low-intensity light anoxygenic or high-intensity oxygenic phototrophs. Consequently, levels of chromophoric dissolved organic matter determine methane oxidation rates. We conclude that chemoclines function as dynamic, light-powered engines for methane removal, sensitive to brownification and climate-induced shifts in stratification.

• Walsh-Vilander, Anna; Vollsnes, Ane; Berntsen, Terje Koren; Fisher, Rosie & Parmentier, Frans-Jan W. (2026). Quantifying Cold Hardening in Arctic-Boreal Vegetation using Differential Thermal Analysis. Full text in Research Archive
• Heuschele, Jan David (2026). Combining citizen science with assisted image classification to determine taxa composition in Norwegian seaweeds. Full text in Research Archive
• Bjerknes, Anne-Line; Burner, Tony; Sjøberg, Mari Heum; Enqvist-Jensen, Cecilie; Lange, Thomas de & Sandberg, Magnus Henrik [Show all 12 contributors for this article] (2026). Skal følelser eller fagkunnskap styre norsk skole? Full text in Research Archive Show summary

  Akademikere mener kjendiser får for mye plass i debatten. Hvordan ville det gått med helsesektoren dersom vi lot de samme folkene definere medisinsk praksis? spør de.

• Rio, Oline Eriksen; Labun, Kornel; Dahal-Koirala, Shiva; Komisarczuk, Anna Zofia; Valen, Eivind & Haapaniemi, Emma Maria (2026). SNIPSNP: precision design of CRISPR reagents. Full text in Research Archive
• Årbogen, Sara Beate Stjern; Sikorski, Pawel; Paulsen, Jonas & Progida, Cinzia (2026). Investigating the Connection Between Surface Topography, Cell Membrane and Nucleus Deformation and its Impact on Chromatin Organization. Full text in Research Archive Show summary

  The field of mechanobiology explores how physical forces and mechanical properties of cells and tissues impact cell development and cell differentiation in health and disease. Physical forces acting on the cell can lead to perturbation of the cell membrane, causing remodeling of the cytoskeleton which can result in reorganization of the nuclear morphology. This is often associated with chromatin reorganization and changes in gene expression. Unraveling the mechanism of mechanical signaling is challenging because it is difficult to study in a controlled manner. Nanofabrication methods enable the generation of precisely engineered surfaces. When combined with advanced microscopy techniques, they can facilitate controlled and systematic studies of the relationships between mechanical forces, nuclear deformation, and chromatin organization. To achieve this we fabricate nanopillar arrays on glass cover slips using electron beam lithography. Using our sample design we can test three variations of the same parameterer within a single experiment, alongside a flat control region for comparison. By seeding cells onto the substrate and allowing them to adhere, we can observe how their interaction with the nanopillars alters nuclear morphology and chromatin organization through advanced microscopy techniques. We will assess the changes in nuclear morphology and look at changes in HP1-α aggregates in the nucleus, which are proteins that are involved in compaction of chromatin.

• Heuschele, Jan David & Johannessen, Ida (2026). Forskning på livet i havet - webinar 3. Full text in Research Archive
• Johannessen, Ida & Heuschele, Jan David (2026). Folkeforskning - Forskning på livet i havet. Full text in Research Archive
• Vøllestad, Leif Asbjørn (2026). Two fish in a large river: grayling and brown trout. A summary. Full text in Research Archive
• Vollsnes, Ane; Fløistad, Inger Sundheim; Hanssen, Kjersti Holt; Ødegaard, Jørgen & Myking, Tor (2026). ForGran - Foryngelse av gran ved planting 2024-2029. Full text in Research Archive
• Vollsnes, Ane; Fløistad, Inger Sundheim; Hanssen, Kjersti Holt; Ødegaard, Jørgen & Myking, Tor (2026). Foryngelse av gran ved planting - ForGran – resultater fra to sesonger. Full text in Research Archive
• Vollsnes, Ane; Geange, Sonya Rita & Vandvik, Vigdis (2026). Boreal and subarctic dwarf shrub contribution to carbon capture early in the growing season. doi: https:/meetingorganizer.copernicus.org/EGU26/EGU26-20380.html. Full text in Research Archive Show summary

  In boreal and subarctic regions, dwarf shrubs may dominate the ground cover in forests as well as open habitats. Therefore, their contribution to the carbon capture in these areas is important to quantify. The length of the growing season impacts greatly on the carbon capture and is also very variable depending on duration of the snow cover as well as daylenghts and temperatures. In a project studying many ecological aspects of dwarf shrubs in four sites in Norway, we compare a coastal and an inland site in the south and the north of the country. The coastal sites typically have less snow than the inland sites, whereas the southern sites have higher mean air temperatures than the northern sites. The extremes of these four sites are then the southern coastal site where the snowless season with favourable temperatures can come in April, versus the northern continental site where snowmelt and favourable temperatures may come in June when there is midnight sun. If the plants from varying locations are differently adapted to start photosynthesising and producing new leaves, it will impact on the seasonal carbon capture. To compare these abilities between sites, we collected plants from each site and grew them in controlled conditions giving them the same winter and spring startup conditions. The dwarf shrubs Calluna vulgaris and Empetrum nigrum are among the species we studied. Repeated measurements of photosynthesis rate, respiration rate and branch lengths were done to investigate the phenology. This presentation will show how the species differed between sites of origin and the results will be discussed with respect to the normal climate at each site.

• Garvang, Even Sletteng; Skogvoll, Vidar & Andersen, Gard Lilledal (2026). Under Kappa #86 - The Thing vs. Mystique, med Gard Lilledal Andersen - Steinhard hud og skuespill. doi: https:/www.underkappa.no/2188463/episodes/19742123-86-the-thing-vs-mystique-med-gard-lilledal-andersen-steinhard-hud-og-skuespill. Full text in Research Archive
• Osnes, Magnus Nygård; Viljugrein, Hildegunn; Dean, Katharine Rose & Wolff, Cecilia Mia (2026). Estimating the relative risk of HPAI presence in wild birds and spillover to commercial poultry farms in Norway: a spatiotemporal risk-mapping approach. Full text in Research Archive Show summary

  Highly pathogenic avian influenza (HPAI) poses an increasing threat to commercial poultry production across Europe. In Norway, six outbreaks in commercial flocks have been recorded since 2021, most in the poultry-dense region of Rogaland county. Despite increased surveillance activities, Norway currently lacks quantitative spatial estimates of HPAI introduction risk to commercial poultry. This study aims to produce a high-resolution, season-specific relative risk map of HPAI presence in wild birds and subsequent spillover risk to commercial poultry farms in Norway. Risk factors were identified through a scoping literature review and assessed for relevance to the Norwegian context in consultation with specialist veterinarians and international collaborators. Risk factor weights were derived using the Best-Worst Method (BWM), a structured expert elicitation approach that enables efficient and consistent pairwise comparisons. Spatial risk layers were constructed at 5x5 km resolution across mainland Norway, including composite seasonal abundance of wild waterfowl and seabirds (based on citizen science data), CORINE land cover classes, human population density, poultry farm and bird density, and historical HPAI detection data. Layers were combined as a weighted mean, producing risk maps for winter, spring, summer, and autumn. Sensitivity to weight uncertainty was assessed through a weight-perturbation approach, and maps were validated against historical HPAI confirmations in wild birds and the locations of the commercial farm outbreaks. The seasonal framework captures the shifting distribution of reservoir host species across Norway's broad latitudinal range. The resulting maps provide a decision-support tool for targeted surveillance prioritisation and biosecurity interventions, and demonstrate how expert-weighted spatial models can be applied in data-limited settings where outbreak frequency is insufficient for purely statistical approaches.

• Heuschele, Jan David & Garvang, Even Sletteng (2026). Hopp Hopp Hoppekreps - A Norwegian children's song about copepods. doi: 10.5281/ZENODO.22082053. Full text in Research Archive Show summary

  "Hopp hopp hoppekreps" is a children’s song about copepods. It aims to bring awareness to one of the most important animal groups in aquatic environments - copepods. The accompanying leaflet has two pages, one that takes the role of a children’s book and one showing the complete song text. In the children’s book, we take some of the verses and illustrate the biological context. The 2 pages are meant to be printed double-sided on sheet of A4 paper, then folded three times, and after a small cut on the indicated line, one can fold it into a mini booklet (or “zine"). The booklet is meant for distribution on science fairs or to be printed out at home as a small children's book.

• Nagy, Nina Elisabeth; Tollefsrud, Mari Mette; Vollsnes, Ane; Timmermann, Volkmar; Børja, Isabella & Hietala, Ari Mikko (2026). Natural regeneration of European ash under severe ash dieback pressure in Fjugstad Nature Reserve, Norway. Full text in Research Archive Show summary

  Key implications for ash regeneration Natural regeneration of ash is still extensive in Fjugstad. Transition into the tree layer is a critical bottleneck under high disease pressure. Local moisture, light environment, growth rate and infection pressure may influence seedling performance. Dense shrub-layer ash with apparently healthy individuals may be useful targets for monitoring and conservation-oriented management. Continued spatial monitoring can identify microsites and individual trees with potential for future ash persistence. Integrate GNSS-based spatial data with moisture and light variables and follow effects of windthrow and canopy opening on new ash regeneration.

• Gundersen, Sveinung; Faci, Pavel Vazquez; Bianchini, Federico; Baskaran, Joshua; Cheneby, Jeanne Marie & Hovig, Eivind [Show all 7 contributors for this article] (2026). fairtracks/omnipy: Omnipy v0.23.1. doi: 10.5281/ZENODO.21999005. Full text in Research Archive
• Gundersen, Sveinung; Bianchini, Federico; Baskaran, Joshua; Chèneby, Jeanne; Fatima, Nazeefa & Hovig, Eivind (2026). fairtracks/fairtracks.net: FAIRtracks.net - ELIXIR3. doi: 10.5281/ZENODO.20089254. Full text in Research Archive
• Tørresen, Ole K. (2026). Gene annotations for copse snail (Arianta arbustorum). doi: 10.5281/ZENODO.22025065. Full text in Research Archive
• Hammerstad, Marta; Gudim, Ingvild; Andersen, Hilde Kristin; Aracena-Solem, Matias & Hersleth, Hans-Petter (2026). Metals and thiols in bacterial defense and survival. Full text in Research Archive
• Grødeland, Gunnveig; Pettersen, Frank O. & Stenseth, Nils Christian (2026). Vaksinepodden - Episode 43 - Svartedauen. Full text in Research Archive Show summary

  Vi husker fra historietimene at Svartedauden kom med et skip til Bjørgvin i 1349. Hva var Svartedauden, og er denne bakterien fortsatt aktuell for en ny pandemi? I denne episoden har vi besøk av Nils Chr. Stenseth, som er professor i biologi og nestleder ved Senter for pandemi- og én-helseforskning ved Universitetet i Oslo. Stenseth har i en årrekke forsket på hvordan bakterien som forårsaket svartedauen - yersinia pestis – har beveget seg rundt i verden. Han har også forsket på hvordan klima kan påvirke både denne bakterien og hantavirus, for eksempel. I studio ellers er som vanlig overlege Frank Olav Pettersen fra Infeksjonsmedisinsk avdeling ved Ullevål, og Gunnveig Grødeland som er professor i immunologi og leder for Senter for pandemi- og en-helseforskning ved Universitetet i Oslo.

• Faci, Pavel Vazquez; Visnovska, Martina; Gundersen, Sveinung & Bianchini, Federico (2026). D5.7 (M12/M24/M36/M48) — Report of "Workflows for omics data integration". doi: 10.5281/ZENODO.20542025. Full text in Research Archive
• Faci, Pavel Vazquez; Visnovska, Martina; Gundersen, Sveinung & Bianchini, Federico (2026). D5.6 (M12/M24) — Report of "Implementation of existing workflows and toolkits for sensitive computing". doi: 10.5281/ZENODO.20541884. Full text in Research Archive
• Faci, Pavel Vazquez; Gundersen, Sveinung; Visnovska, Martina & Bianchini, Federico (2026). D5.5 (M24/M36) — Report of "Framework for achieving import of non-sensitive reference data and software components obtained from external sources and deployed infrastructure for ELIXIR BioContainers repository in secure compute environments". doi: 10.5281/ZENODO.20541631. Full text in Research Archive
• Bieker, Vanessa Carina; Cerca, José; Battlay, Paul; Falahati-Anbaran, Mohsen; Sharma, Amit & Diaz, Patricia Jaramillo [Show all 21 contributors for this article] (2026). Exploring the genomic basis of adaptive leaf variation in the of Galapagos giant daisies (Scalesia). Full text in Research Archive Show summary

  Scalesia (Asteraceae) is the largest endemic plant genus of the Galapagos archipelago and an example of adaptive radiation. While Scalesia species are highly varied in habit and morphology, most remarkable is their variety of leaf shapes, especially in the differential presence of leaf lobing/serration, a derived trait that evolved multiple times as a likely adaptation to the islands' hot and dry equatorial climate. Using population-level genomic data from 396 individuals representing all 15 recognized Scalesia species, we characterize this young radiation (around 1 Mya), and reveal that their substantial morphological divergence and ecological specialization are primarily based on shared genetic variation. To further elucidate the repeated adaptive evolution of leaf lobing in Scalesia, we integrated genomic and leaf morphometric data, with transcriptomes from different developmental stages, and via population genomic scanning concluded that leaf lobing evolved through diversifying selection. Natural selection occurred independently on different regulators in the pathway controlling development of adaxial-abaxial leaf polarity, highlighting the importance of the founder populations' high genetic diversity maintained via allopolyploidy. Our findings have implications for the conservation of Scalesia's threatened biodiversity, as unexpectedly high intra-specific genetic structure and long-term isolation among populations indicate widespread nascent speciation.

• Ottersen, Geir (2026). Experiences with LLM tools for scientific writing and literature review. Full text in Research Archive Show summary

  I’m sharing my experiences with applying Large Language Model (LLMs) to enhance scientific writing and literature review. The LLM branch of Artificial Intelligence is now totally changing the science writing process and we all must relate to this. I am no expert and this is not a course, but I’ve spent some time trying to get a grip on how to use standard LLMs (Copilot, ChatGPT, etc.) and a couple of more specialized ones (SciSpace, Elicit) to improve my scientific writing and literature review workflow. I’m sure some of you also have done this, but I miss constructive guidelines or recommended tools. Maybe this can be a starting point for exchanging ideas? My presentation has three main parts: i) Motivation – why invest time in LLMs, ii) General tips including better prompting (reasoning strategies, iterative prompting, personalization….) and applying ChatGPT Custom GPTs, and iii) examples of my uses including help to produce abstract, referee work, early stage of literature review, and popular science article from project description.

• Ottersen, Geir & Pascual, Alvaro de (2026). SEACLIM WP4- Ocean Climate Indicators Achievements and Workplan for 2026. Full text in Research Archive
• Sanden, Monica; Ager-Wick, Eirill; Bodin, Johanna Eva; Duale, Nur; Jevnaker, Anne-Marthe Ganes & Prydz, Kristian [Show all 8 contributors for this article] (2026). Assessment of genetically modified soybean MON 94313 for food and feed uses, import and processing under Regulation (EC) No 1829/2003 (application EFSA-GMO-NL-2022-176). VKM Bulletin. 9(2026), p. 1–14. Full text in Research Archive Show summary

  Genetically modified event MON 94313 was developed through Agrobacterium-mediated transformation of soybean tissues. The plant expresses the dmo, pat, ft_t.1 and tdo genes coding for the proteins DMO, PAT, FT_T.1 and TDO proteins which provide tolerance to dicamba (3,6-dichloro-2-methoxybenzoic acid), glufosinate (2-amino-4- (hydroxymethylphosphinyl) butanoic acid), 2,4-D (2,4-dichlorophenoxyacetate) and mesotrione (2-[4-(methylsulfonyl)-2-nitrobenzoyl]-1,3-cyclohexanedione) herbicides, respectively. The scientific documentation provided in the application for genetically modified soybean MON 94313 is adequate for risk assessment, and in accordance with EFSA guidance on risk assessment of genetically modified plants for use in food or feed. The VKM GMO panel does not consider the introduced modifications in event MON 94313 to imply potential specific health or environmental risks in Norway, compared to EU-countries.

• Sanden, Monica; Ager-Wick, Eirill; Bodin, Johanna Eva; Duale, Nur; Jevnaker, Anne-Marthe Ganes & Prydz, Kristian [Show all 8 contributors for this article] (2026). Assessment of genetically modified soybean GMB151 x DAS-44406 6 for food and feed uses, import and processing under Regulation (EC) No 1829/2003 (application GMFF-2024-21774). VKM Bulletin. 2026(8), p. 1–15. Full text in Research Archive Show summary

  GMB151 x DAS-44406-6 soybean was developed by crossing the single parental lines GMB151 and DAS-44406-6 using traditional breeding methods. No new genetic modification was introduced in GMB151 x DAS-44406-6 soybean. The DNA inserts in GMB151 x DAS-44406-6 soybean are inherited from parental lines GMB151 and DAS-44406-6. The soybean product GMB151 x DAS44406 confers nematode resistance and herbicide tolerances. Each single trait contributes specific benefits to the final stacked trait product. GMB151 soybean produces the Cry14Ab-1 protein, a crystal protein derived from Bacillus thuringiensis, which confers resistance to plant parasitic nematodes. GMB151 also produces a modified 4-hydroxyphenylpyruvate dioxygenase (HPPD-4) enzyme derived from Pseudomonas fluorescens, which confers tolerance to HPPD inhibitor herbicides such as isoxaflutole. DAS-44406-6 soybean produces phosphinothricin acetyltransferase (PAT), aryloxyalkanoate dioxygenase-12 (AAD-12), and double mutant 5-enolpyruvylshikimate-3-phosphate synthase (2mEPSPS). PAT protein, derived from Streptomyces viridochromogenes, confers tolerance to glufosinate herbicides. AAD-12 protein, derived from Delftia acidovorans, confers tolerance to 2,4-D herbicides. 2mEPSPS protein, derived from Zea mays, confers tolerance to glyphosate herbicides. The scientific documentation provided in the application for genetically modified soybean GMB151 x DAS-44406-6 is adequate for risk assessment, and in accordance with EFSA guidance on risk assessment of genetically modified plants for use in food or feed. The VKM GMO panel does not consider the introduced modifications in soybean GMB151 x DAS-44406-6 to imply potential specific health or environmental risks in Norway, compared to EU-countries. The EFSA opinion is adequate also for Norwegian considerations. Therefore, a full risk assessment of soybean GMB151 x DAS 44406-6 was not performed by the VKM GMO Panel.

• Mysterud, Atle (2026). CWD og villreinforvaltning på Hardangervidda og i Nordfjella - hva har vi lært og hvordan ser fremtiden ut? Full text in Research Archive
• Sundfjord, Arild; Hallanger, Ingeborg G.; Halterskjær, Hans Erik; Christensen, Jacob Max; Czyz, Ceslav & Dinh, van Khuong [Show all 19 contributors for this article] (2026). Arctic Ocean 2025 A-TWAIN + HiAOOS cruise report: 22 October - 10 November 2025 (cruise ID:2025712). Full text in Research Archive Show summary

  Cruise report from the Norwegian Polar Institute's Arctic Ocean cruise 2025. The report details work done and data/samples collected, plus recovery and deployment of deep ocean instrument moorings. All data collected by the Norwegian Polar Institute and all bottle sample data from UiT - The Arctic University of Tromsø during the cruise are made available through the Norwegian Polar Data Centre at DOI https://doi.org/10.21334/npolar.2025.1c59d3fb.

• Hu, Xian; Margadant, Felix & Bakke, Oddmund (2026). Micro-stepping extended focus reduces photobleaching and preserves structured illumination super-resolution features. Show summary

  Despite the progress made in fast scan units, confocal systems still have insufficient temporal resolution for many volume imaging requirements, such as tracking movement of membrane vesicles in live cells. Researchers might sacrifice certain imaging modalities to achieve better performance in temporal resolution. This may result in imaging artifacts such as undersampling artifacts and limit the amount of analyzable data. We propose a imaging modality producing fast projections from the field of depth which will shorten the imaging time by approximately an order of magnitude compared to volume imaging. The implementation requires merely a minimum two synchronized control signals that drive a piezo stage and trigger the camera exposure, a third, optional signal, blanks the laser output when the stage is in motion which mildly improves the stability and repeatability of the exposure. The device generating the signals has been tested on spinning disk confocal as well as on instant structured- illumination-microscopy (iSIM) microscopes. Our calibration images show that the approach provides highly repeatable and stable imaging conditions and does enable photometric measurements of the acquired data, in both the regular spinning disk setup as well as in the iSIM configuration.While light sheet microscopes can provide even faster projections of the same volume, the presented method provides more homogeneous optical sectioning and maintains the structured illumination characteristics.

• Skjerve, Hilde; Strand, Martin Frank Fjeldbu; Sørensen, Anette; Braaum, Lars Erik & Hasle, Emil Trygve (2026). Course-Aligned AI Chatbot in Higher Education. Full text in Research Archive
• Bianchini, Federico (2026). Create, customise, and maintain a Data Management Plan. doi: 10.5281/ZENODO.18376175. Full text in Research Archive
• Bianchini, Federico; Pulido, Toni Hermoso; Juty, Navtej; Litou, Zoi; Åkerström, Wolmar Nyberg & Moura, Bruna Piereck (2026). Interoperability Workshop Session: Co-located with ELIXIR Training Platform. doi: 10.5281/ZENODO.19254477. Full text in Research Archive
• Bianchini, Federico (2026). D5.4 (M48) - Report of recommended implementation strategy for FAIR sharing of human data (an ELIXIR Norway ELIXIR3 deliverable). doi: 10.5281/ZENODO.19278363. Full text in Research Archive
• Bösl, Korbinian & Bianchini, Federico (2026). D3.1 (M48) - Report Data Stewardship Wizard instance and releases and updates of the knowledge resources for Norwegian users (an ELIXIR Norway ELIXIR3 deliverable). doi: 10.5281/ZENODO.19257464. Full text in Research Archive
• Bösl, Korbinian & Bianchini, Federico (2026). D3.2 (M48) Updated Report on annual training events and meetings for professional Data Stewards (an ELIXIR Norway ELIXIR3 deliverable). doi: 10.5281/ZENODO.19257068. Full text in Research Archive
• Bianchini, Federico & Pierfederici, Elisa (2026). Create and Maintain a Data Management Plan with FAIR Wizard Norway. doi: 10.5281/ZENODO.19130740. Full text in Research Archive
• Bianchini, Federico; Bösl, Korbinian & Kalaš, Matúš (2026). D3.3 (M48) - Report on curation in core ELIXIR registries. doi: 10.5281/ZENODO.19249870. Full text in Research Archive
• Folkehelseinstituttet; Berstad, Paula Marianna; Helleve, Arnfinn; Indseth, Thor; Kløvstad, Hilde & Knudsen, Ann Kristin Skrindo [Show all 8 contributors for this article] (2026). Temautgave av Folkehelserapporten: De viktigste folkehelseutfordringene. Full text in Research Archive Show summary

  I denne rapporten gir FHI en oversikt over helsetilstanden i Norge, og faktorer som påvirker den. Vi går gjennom både overordnede samfunnsforhold, store folkehelseutfordringer, og helsetrusler. Noen særlig viktige samfunnsforhold som har stor påvirkning på folkehelsen i dag og framover, er at vi har en aldrende befolkning, som setter press på helsetjenestene og samfunnets bærekraft både ved at antallet eldre øker, og at andelen øker opp mot den arbeidsføre befolkningen. Sosial ulikhet i helse er fortsatt en folkehelseutfordring og blir ytterligere komplisert av innvandring. Svekket internasjonalt samarbeid om beredskap, en urolig geopolitisk situasjon, digitalisering av samfunnet og endrede holdninger til kunnskap påvirker folkehelsearbeidet i Norge. Folkehelsen og livskvaliteten i Norge er god. Vi lever lenge og andelen friske leveår har økt. Lengre levetid bidrar imidlertid til at år levd med helsetap også øker. Ikke-smittsomme sykdommer er hovedårsaken til sykdomsbyrden i Norge. Vi trekker i denne rapporten særlig fram to utfordringer: Psykiske lidelser blant barn og unge har økt, særlig etter 2010, og fortsetter å øke. Dette påvirker livskvalitet gjennom hele livsløpet, og samfunnsdeltakelse i utdanning og arbeidsliv. Sosiale ulikheter forsterker disse effektene. Tidlig forebygging av psykiske lidelser hos unge kan gi store gevinster for samfunnsdeltakelse og folkehelse. En annen utfordring er sykdom i en aldrende befolkning. En stadig høyere andel lever mange år med sykdom, og oftere med flere sykdommer, hvor hjerte- og karsykdommer, kreft og demens utgjør en vesentlig del. Flere av sykdommene innenfor disse hovedgruppene er i stor grad forebyggbare. Framskrivninger av norske helseutgifter viser at demens, hjerneslag og diabetes vil være de viktigste kostnadsdriverne fram mot 2050. Helsetrusler omfatter både akutte hendelser og langsiktige utviklingstrekk som kan påvirke folkehelsen. De viktigste truslene fremover er komplekse og henger sammen med globale endringer. Pandemier og smittsomme sykdommer vil fortsatt kunne være store utfordringer, forsterket av blant annet global mobilitet, urbanisering og svekket internasjonalt samarbeid. Antimikrobiell resistens (AMR) er en langsomt voksende trussel som kan gjøre behandling av infeksjoner vanskelig og true moderne medisinsk praksis. Forhold som svekker vaksinasjonsdekning kan bidra til økt risiko for utbrudd av alvorlige smittsomme sykdommer, flere sykehusinnleggelser, høyere dødelighet og økt antibiotikabruk. Ellers trekker vi også fram sårbarhet knyttet til drikkevann, faren for kjemikaliehendelser og syntetisk biologi som trusler som krever god beredskapsevne. Klimaendringer er vurdert som en forsterker av andre trusler. Det ligger store muligheter i å forebygge uhelse. Forebygging er den mest kostnadseffektive strategien for å redusere sykdomsbyrden. Det er behov for å styrke kunnskapen om effektive folkehelsetiltak og forebyggende tiltak i helsetjenestene. For en stor del av sykdomsbyrden er de underliggende risikofaktorene ikke kjent eller forstått, og her ligger det potensial for å forebygge sykdom gjennom å skaffe kunnskap om risiko- og årsaksfaktorer. God overvåking og beredskap, internasjonalt og tverrsektorielt samarbeid og forebyggende tiltak er avgjørende for å holde forekomsten av smittsomme sykdommer lav og redusere konsekvensene av helsetrusler. Fremtidens folkehelsearbeid må styrke den tverrsektorielle tilnærmingen og se på etablerte utfordringer og akutte helsetrusler i sammenheng.

• Mysterud, Atle (2026). Hunting and management of chronic wasting disease in cervids in North America and Europe. Full text in Research Archive
• Supraha, Luka; Heuschele, Jan David & Leu, Eva (2026). From Ice to Open Water: Response of Arctic Mircoalgae to Changing Environmental Drivers. Full text in Research Archive
• Kunisch, Erin Hye Soo; Furness, Lydia Hildebrand; Buss, Danielle Lia; Sabin, Richard; Star, Bastiaan & Barrett, James Harold (2026). A glimpse under the surface: untangling the historical food web of the Steller’s sea cow. Full text in Research Archive
• Mysterud, Atle (2026). Ti år med skrantesyke: Hjalp det å skyte 2000 villrein? Full text in Research Archive Show summary

  15. mars er det ti år siden det første tilfellet av skrantesyke ble oppdaget blant villrein. At 2000 villrein i Nordfjella ble skutt, skapte rystelser i norsk naturforvaltning. Hva har vi lært, og hvor står vi nå?

• Mysterud, Atle (2026). Adaptive management of chronic wasting disease in cervids. Full text in Research Archive
• Melteig, Elina; Vollsnes, Ane & Fløistad, Inger Sundheim (2026). Den virkelige grunnen til at juletreet drysser – og slik unngår du det. [Internet]. forskning.no. Full text in Research Archive Show summary

  Du vanner og vanner, men treet drysser likevel. En forsker forklarer hvorfor vanningen ikke alltid hjelper.

• Heuschele, Jan David & Johannessen, Ida (2026). Forskning på livet i havet - Webinar 2. Full text in Research Archive
• Andersen, Oddgeir; Veiberg, Vebjørn & Mysterud, Atle (2026). Gjennomgang av termisk undersøkelsen. Full text in Research Archive
• Andersen, Oddgeir; Veiberg, Vebjørn & Mysterud, Atle (2026). Hvordan påvirker bruk av termisk utstyr antall observerte dyr? Full text in Research Archive
• Aarnes, Halvor & Jørgensen, Marte Holten (2026). blomsterformel – Store norske leksikon. Store Norske Leksikon (Nettutgaven). Full text in Research Archive Show summary

  Blomsterformel er en tekst som viser strukturen og oppbygningen av en blomst. Når man beskriver en blomst på blomsterformel så angis de ulike delene av blomstene med en fast kode og deretter antall. Det er også koder for sammenvoksing, symmetri og plassering.

• Foote, Andrew David (2026). Museum collections provide a temporal record of past genetic variation. Proceedings of the National Academy of Sciences of the United States of America (PNAS). ISSN 0027-8424. 123(2). doi: 10.1073/pnas.2530586122. Full text in Research Archive Show summary

  Not applicable

• Aguilar-Díaz, Alejandro; Sorribes-Daudén, Raquel; Vanacloig-Pedrós, Elena; Martínez-Pastor, María Teresa; Puig, Sergi & Peris, David (2025). Tracking genomic adaptation to copper stress in yeast using an integrated bioinformatics pipeline. Full text in Research Archive
• Peris, David; Munoz, Sara Orellana; Csoboz, Balint; Sorribes-Daudén, Raquel; Vanacloig-Pedrós, Elena & Aguilar-Díaz, Alejandro [Show all 11 contributors for this article] (2025). FunGIALab: Connecting Fungal Diversity, Evolution, and Biotechnological Applications. Full text in Research Archive
• Riis-Pedersen, Christine; Carlsen, Eira Catharine Lødrup; Hessen, Dag Olav; Lejzerowicz, Franck Laurent Patrick; Andersen, Tom & Dörsch, Peter [Show all 8 contributors for this article] (2025). Microbial drivers of methane cycling in meromictic as compared to holomictic lakes. Full text in Research Archive
• Carlsen, Eira Catharine Lødrup; Wei, Jing; Lejzerowicz, Franck Laurent Patrick; Ippach, Mats Rouven; Pismeniuk, Anfisa & Kjær, Sigrid Trier [Show all 10 contributors for this article] (2025). Greenhouse gas production kinetics and metabolic traits in thawing permafrost peat. Full text in Research Archive Show summary

  While numerous drivers of greenhouse gas emission (GGE) have been suggested to drive variabilities across thawing landscapes, experimental validations are still widely lacking . Here, I will present results from several experimental studies capturing drivers of GGE across thawing permafrost landscapes like redox, organic matter and microbial source community. Our findings reveal clear responses of the greenhouse gases to redox conditions across the landscape. CO2 production showed a drastic decline when O2 dropped below 100 μM; specifically, under anoxic conditions, CO2 yield and maximum net production rates decreased by around 90 % compared to oxic conditions. CH4 levels remained consistent across O2 gradients, until at least 6 months upon thawing. Functional groups like N2O reducers, fermenters, denitrifiers, and sulfur reducers increased under anoxic conditions, and the reduced CO2 production rates and yields under anoxic conditions were reflected by genomic changes towards reduced central metabolic efficiency. Our data thus points towards critical GGE thresholds under suboxic conditions across thawing landscapes. Moreoever, gas dynamics seem to be primarily influenced by permafrost conditions rather than source community colonization. Our experiments provide increased knowledge on the variable GGE across thawing permaforst landscapes influenced by variable redox conditions and permafrost´s organic matter legacy.

• Årbogen, Sara Beate Stjern; Sikorski, Pawel; Paulsen, Jonas & Progida, Cinzia (2025). Investigating the Connection Between Surface Topography, Cell Membrane and Nucleus Deformation and its Impact on Chromatin Organization and Gene Expression. Full text in Research Archive Show summary

  Changes in nuclear mechanics and shape are both considered hallmarks of disease, including cancer. Abnormal nuclear shape is linked with chromatin reorganization, and impacts gene expression. Physical forces that act on the cell can trigger remodelling of the cell cytoskeleton, which in turn can alter the nuclear shape. Knowledge of the relationship between nuclear deformation, chromatin reorganization and gene expression can be exploited for many application within biomedical research. However, revealing these relationships are challenging because it is difficult to study in a controlled manner. We address this challenge using nanofarbication methods to make substrates for cells to induce nuclear deformation, coupled with readouts on DNA condensation and gene expression.

• Årbogen, Sara Beate Stjern; Sikorski, Pawel; Paulsen, Jonas & Progida, Cinzia (2025). Investigating the Connection Between Surface Topography, Cell Membrane and Nucleus Deformation and its Impact on Chromatin Organization and Gene Expression. Full text in Research Archive Show summary

  Changes in nuclear mechanics and shape are both considered hallmarks of disease, including cancer. Abnormal nuclear shape is linked with chromatin reorganization, and impacts gene expression. Physical forces that act on the cell can trigger remodelling of the cell cytoskeleton, which in turn can alter the nuclear shape. Knowledge of the relationship between nuclear deformation, chromatin reorganization and gene expression can be exploited for many application within biomedical research. However, revealing these relationships are challenging because it is difficult to study in a controlled manner. We address this challenge using nanofarbication methods to make substrates for cells to induce nuclear deformation, coupled with readouts on DNA condensation and gene expression.

• Olsen, Are; Årthun, Marius; Skodvin, Knut Einar; Dodd, Paul; Jentoft, Sissel & Renaud, Paul [Show all 16 contributors for this article] (2025). Polhavet Arctic Ocean 2050 - Science Plan. Full text in Research Archive
• Ottersen, Geir (2025). Er klimautfordringene den største trusselen for skreien? Full text in Research Archive
• Ottersen, Geir (2025). Impacts of Climate Change on marine Ecosystems 2025. Full text in Research Archive Show summary

• Bianchini, Federico & Bösl, Korbinian (2025). Data Stewardship Wizard - beyond the end-user. doi: 10.5281/ZENODO.14747326. Full text in Research Archive
• Nazeefa, Fatima; Bianchini, Federico; Leon, Arturo Vera Ponce de; Åberg, espen; Ostrop, Jenny & Hjerde, Erik [Show all 10 contributors for this article] (2025). ELIXIR-Norway-Training/DMP-writing-workshop: DMP Workshop March 2025. doi: 10.5281/ZENODO.15052316. Full text in Research Archive
• Bianchini, Federico & Kvale, Live Håndlykken (2025). Create, customise, and maintain a Data Management Plan. doi: 10.5281/ZENODO.14697229. Full text in Research Archive
• Jenner, Ronald A.; Casewell, Nicholas R. & Undheim, Eivind Andreas Baste (2025). Venom versus poison: delivery mode matters. Trends in Ecology & Evolution. ISSN 0169-5347. 40(11), p. 1047–1047. doi: 10.1016/j.tree.2025.09.019. Full text in Research Archive
• Ryvarden, Leif (2025). Aphyllophorales of Africa 64 - Fungi from Zimbabwe on dry sticks above the ground. Synopsis fungorum. ISSN 0802-8966. 52, p. 87–88. Full text in Research Archive
• Mokni, Ridha El & Ryvarden, Leif (2025). Further records and an updated checklist of the genus Ganoderma P. Karst. (Ganodermataceae, Polyporales) in Tunisia and northern Africa. Synopsis fungorum. ISSN 0802-8966. 52, p. 102–107. Full text in Research Archive
• Mokni, Ridha El & Ryvarden, Leif (2025). Vitreoporus dichrous (Fr.) Zmitr. (Meruliaceae, Polyporales) new to Tunisian poroids, third report to North African after more than 100 years. Synopsis fungorum. ISSN 0802-8966. 52, p. 97–101. Full text in Research Archive
• Mokni, Ridha El & Ryvarden, Leif (2025). Laetiporus discolor Burds. (Laetiporaceae, Basidiomycota) an addition to Mediterranean poroids from Tunisia. Synopsis fungorum. ISSN 0802-8966. 52, p. 91–96. Full text in Research Archive
• Ryvarden, Leif (2025). Aphyllophorales of Africa 65 – Two new Aleurodiscus species from Africa. Synopsis fungorum. ISSN 0802-8966. 52, p. 89–90. Full text in Research Archive
• Spirin, Viacheslav & Ryvarden, Leif (2025). Aphyllophorales of Africa 63 – More wood inhabiting species from Zimbabwe. Synopsis fungorum. ISSN 0802-8966. 52, p. 80–86. Full text in Research Archive
• Ryvarden, Leif (2025). Some new Australian polypores. Synopsis fungorum. ISSN 0802-8966. 52, p. 77–79. Full text in Research Archive
• Ryvarden, Leif (2025). Heterobasidiomycetes of Scandinavia – a preliminary survey. Synopsis fungorum. ISSN 0802-8966. 52, p. 5–76. Full text in Research Archive
• Ottesen, Vibeke Kennair (2025). Terrorism, Sexual Selection and. In Shackelford, Todd (Eds.), Encyclopedia of Religious Psychology and Behavior. Springer. ISSN 9783031389719. p. 1–4. doi: 10.1007/978-3-031-38971-9_1918-1. Full text in Research Archive
• Ottesen, Vibeke Kennair (2025). Honour Killings. In Shackelford, Todd (Eds.), Encyclopedia of Religious Psychology and Behavior. Springer. ISSN 9783031389719. p. 1–4. doi: 10.1007/978-3-031-38971-9_281-1. Full text in Research Archive
• Gruber, Christian W.; Beets, Isabel; Boudreault, Pierre‐Luc; Bolzani, Vanderlan da S.; Carlsson, Jens & Fernandes, Pedro A. [Show all 17 contributors for this article] (2025). Biodiversity2Drugs—Renaissance of exploring nature‐derived peptides for GPCR ligand discovery. British Journal of Pharmacology. ISSN 0007-1188. 182(16), p. 3694–3694. doi: 10.1111/bph.70072. Full text in Research Archive
• Rounge, Trine Ballestad & Paulsen, Jonas (2025). Highly sensitive method captures rare RNAs in blood to search for disease. Nature. ISSN 0028-0836. 641(8063), p. 599–600. doi: 10.1038/d41586-025-01127-7. Full text in Research Archive
• Slagsvold, Tore & Wiebe, Karen (2025). On heterospecific learning in birds – response to Hämäläinen et al. Behavioral Ecology and Sociobiology. ISSN 0340-5443. 79(9). doi: 10.1007/s00265-025-03622-3. Full text in Research Archive
• Hyvärinen, Olli Petteri; Eiler, Alexander; Werner, Even; Gagnon, Karine; Thormar, Jonas & Mørch, Mikkel Martinussen (2026). Biodiversity patterns and blue carbon characteristics of Zostera marina meadows in the Oslofjord. Linking sediment carbon stocks, stable isotopes, and eDNA-derived faunal communities across citizen-science and field-sampled eelgrass meadows. Universitetet i Oslo. Full text in Research Archive Show summary

  Seagrass meadows are coastal foundation habitats that support biodiversity and store organic carbon in sediments, a process often referred to as blue carbon storage. However, both biodiversity and sediment carbon storage can vary strongly among meadows, and it remains unclear how local meadow structure, hydrodynamic exposure, organic-matter sources, and associated fauna interact in temperate eelgrass systems. This thesis investigated biodiversity and blue carbon characteristics of \emph{Zostera marina} meadows in the Oslofjord, Norway. The study combined two complementary approaches: citizen-science-based environmental DNA (eDNA) water sampling across eelgrass meadows and seasons, and researcher-led field sampling at three meadows along an inner-outer Oslofjord gradient. The field-sampled meadows represented contrasting coastal settings: an inner-fjord meadow at Fornebu, a sheltered meadow near Sætre/Sandspollen, and a more wave-exposed outer-fjord meadow at Holmestrand. The water eDNA dataset provided broad spatial and seasonal coverage, but ecological interpretation was limited by uneven sampling and read-depth loss after filtering. After taxonomic partitioning of the cytochrome c oxidase I (COI) metabarcoding dataset, only 20.5\% of reads were retained as faunal reads, while 79.5\% were classified as non-faunal reads. The retained faunal water eDNA dataset did not show clear winter-spring or Oslofjord-section structure. Instead, it contained a mixed coastal signal, including pelagic planktonic taxa and benthic or soft-sediment-associated taxa. In contrast, the non-faunal fraction showed clearer winter-spring structuring, largely associated with microalgal and protist groups. This indicates that broad COI water eDNA can capture useful biodiversity signals, but also that faunal and non-faunal datasets should be separated before ecological interpretation. The strongest ecological patterns were found in the field-measured meadows. The sheltered Sætre/Sandspollen meadow had continuous eelgrass cover, low sediment bulk density, high and consistent organic carbon stocks, and the highest apparent seagrass-like carbon contribution. The more wave-exposed Holmestrand meadow was patchier and had higher bulk density, lower organic carbon stocks, and the lowest apparent seagrass-like carbon contribution. The inner-fjord Fornebu meadow had intermediate sediment carbon stock, bulk density, and apparent seagrass-like carbon contribution, but showed greater within-meadow variability. Stable isotope composition supported these meadow-level differences and indicated variation in both carbon-source characteristics and assimilated nitrogen among meadows. Benthic eDNA showed clear separation between seagrass-blade epifaunal communities and sediment-core infaunal communities. Infaunal communities were most strongly associated with sedimentary gradients and were dominated by sediment-associated annelids, including lugworms and other taxa linked to deposit feeding, burrowing, sediment reworking, and bioirrigation. In contrast, the epifaunal signal was dominated more strongly by sessile or surface-associated taxa, including barnacles, bryozoans, and hydrozoans, rather than by mobile mesograzers. Overall, this thesis shows that eelgrass meadows in the Oslofjord can differ substantially in meadow structure, sediment carbon characteristics, stable isotope composition, and associated benthic fauna. The results support a descriptive interpretation in which blue-carbon characteristics and benthic biodiversity vary together at local meadow scale, particularly through the association between sediment conditions and infaunal community structure. Broader inference about Oslofjord-wide seasonal biodiversity patterns will require more balanced repeated sampling but the study demonstrates the value of combining citizen-science water eDNA with targeted field measurements when assessing biodiversity and blue carbon in eelgrass meadows.

• Dahal-Koirala, Professor Pål Falnes, Dr. Shiva & Naseri, Nafasgol (2026). Main title: Investigation of on-target Chromosomal deletions and loss during HDR-enhanced CRISPR-Cas9 correction of a CARMIL2 point mutation in patient-derived T cells Subtitle: On-target genomic integrity after CARMIL2 gene correction. Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract will be published: 2028-08-01

• Billah, Vladimir Gusarov, Maxwell Kelvin & Billah, Hilda Ansomaa Jakin Osei-Mireku, Vladimir Gusarov, Maxwell Kelvin (2026). Rove Beetle Diversity in Ghana. Population Comparison of Selected Species and Phylogeny of the Subtribe Medonina (Insecta: Coleoptera: Staphylinidae: Paederinae). Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract and files will be published: 2029-06-29

• Undheim, Evind Andreas Baste; Vøllestad, Leif Asbjørn & Syvertsen, Knut Steinar Tollefsrud (2026). Investigating the venom of the lesser weever. Universitetet i Oslo. Full text in Research Archive Show summary

  Abstract Fish make up one of the most diverse groups of vertebrates, and venom is thought to have evolved independently in teleosts at least 19 different times. Despite this large diversity, their venom remains comparatively understudied and characterization has only been done for a small number of species. Most of the venomous teleost species deliver their venom through relatively simple structures, such as dorsal and opercular spines, suggesting a recurrent defensive strategy, rather than more specialized offensive systems. The weever fish Echiichtys vipera is a venomous fish that has recently established itself in Norwegian waters, and it provides an opportunity to investigate the composition and evolution in such a defensive venom system. This study aims to characterize key components of E. vipera venom by, (i) investigating whether venom composition and expression differ between the dorsal and opercular spines, (ii) assessing potential differences between Norwegian, Italian and English individuals, and (iii) examining similarities in composition and phylogeny between E. vipera venom and defensive venoms from other teleost species. To address these aims, venom and tissues samples were collected form Norwegian and Italian individuals, and a whole-genome assembly from an English individual was obtained from NCBI GenBank. These samples were analyzed using genome-guided transcriptomics and LC-MS/MS-based bottom-up proteomics, combined with database-assisted identification as well as comparative phylogenetic analysis. The resulting data suggest that dorsal and opercular venom express broadly similar set of putative venom-associated proteins, including nattectin-like lectins, Natterin-like, PLA2 -like, hyaluronidase-like and SNTX-like proteins, supporting the view that these spines might have originated from similar epidermal protein-secreting cell tissues. Comparison between Norwegian and Italian individuals indicate that the main putative toxin families are conserved in both populations, which is consistent with the theory of defensive venoms being subject to negative selection to maintain the pain-inducing effect. The Phylogenetic analysis shows that E. vipera SNTX-like proteins with high support cluster together with stonefish toxin-like proteins found in other teleosts and another smaller group of SNTX-like proteins cluster together with B30.2/SPRY domain-containing proteins from non-venomous fish. This supports the hypothesis of SNTX-like proteins potentially stemming from a non-toxic protein. Together these findings help characterize the molecular components of E. vipera venom and places the SNTX-like proteins in a broader evolutionary teleost context.

• Star, Bastiaan; Teske, Peter & Grønbekk, Justina (2026). SARDINE-SEQ: Population structure of southern African sardines investigated by whole-genome sequencing. Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract and files will be published: 2027-07-01

• Naseri, Nafasgol; Dahal-Koirala, Shiva; Haapaniemi, Emma Maria & Falnes, Pål (2026). Investigation of on-target Chromosomal deletions and loss during HDR-enhanced CRISPR-Cas9 correction of a CARMIL2 point mutation in patient-derived T cells. University of Oslo (UiO). Full text in Research Archive
• Eiler, Alexander; Stensrud, Eivind & Røstum, Tarjei Gaulen (2026). Fur and Feathers, Cod to Wrasse. Changes in a top predator’s diet, trophic position, and top-down effects in the Oslofjord and Skagerrak. Universitetet i Oslo. Full text in Research Archive Show summary

  Coastal food webs in the Oslofjord and Skagerrak have changed over the recent decades, driven by anthropogenic stressors such as overfishing, bottom trawling, increased eutrophication, and climate change. The regional collapse of Atlantic cod (Gadus morhua) has been associated with cascading effects on prey communities, which remain poorly understood. Understanding the top-down role of generalist predators such as the great cormorant (Phalacrocorax carbo) and the harbour seal (Phoca vitulina) is critical for assessing food web dynamics to establish conservation efforts, particularly following the 10-year fishing ban and the establishment of no-take zones in the Oslofjord on 1 January 2026. This study assessed the diet of the great cormorant and the harbour seal using a dataset spanning 14 years (2012–2025), using dual-marker dietary DNA metabarcoding (MiFish and COI Leray-XT) from intestinal samples, complemented by stable isotope analysis to assess trophic position. Both predators showed clear dietary partitioning, with diet composition varying significantly across seasons: the great cormorant diet was dominated by benthic prey, while the harbour seal diet predominantly relied on pelagic species, with peak Atlantic herring (Clupea harengus) and Atlantic cod detections occurring in the autumn and winter. Atlantic herring (Clupea harengus) was detected in up to 47% of harbour seal samples, substantially higher than reported in previous otolith-based studies from the same region. The great cormorant diet revealed a significant decline in Atlantic cod detections, concurrent with a significant increase in wrasse species, consistent with a top-down trophic cascade potentially driven by the regional cod collapse and mesopredator release. The harbour seal showed marginally higher δ15N values than the great cormorant, suggesting a slightly higher trophic position. Dietary metabarcoding provides a year-round, high-resolution approach for monitoring predator diet, complementing conventional methods and capture seasonal dietary signals missed by summer-biased hard part analyses. A collaboration with local hunters donating samples enabled the establishment of a dietary baseline, which provided a critical reference point for monitoring ecosystem recovery following the 2026 Oslofjord fishing ban, enabling the detection of dietary shifts should Atlantic cod populations recover under reduced fishing pressure.

• Andvik, Clare Margaret (2026). Multiple stressors in Norwegian killer whales: Integrating the effect of chemical pollution with other anthropogenic stressors. Universitetet i Oslo. Full text in Research Archive Show summary

  Stress is a natural part of life. However, whilst organisms have evolved mechanisms over millions of years to cope with natural stressors in their environment, humans have, in the space of a few decades, created a multitude of new stressors that threaten our natural world. This thesis assessed the effect of three stressors – chemical pollution, whale watching tourism, and nutritional stress – on an ecologically, economically and socially important species: the killer whale (Orcinus orca). We used a combination of field and laboratory studies, and developed new analytical techniques for multiple analyses in tiny tissue samples. We first established baseline pollutant and exposure data for Norwegian killer whales. We found that whilst long-regulated “legacy” pollutants dominated the pollutant load, unregulated “emerging” contaminants were an increasing risk, and could also biomagnify and be passed from mother to offspring. We then found potential effects of both pollutants and whale watching on hormone levels, and the expression of stress and immune-related genes. The effect of contaminants on cortisol was further amplified during high whale watching periods, with the strongest stress response in whales with better nutritional status. This thesis presents an interdisciplinary framework for assessing the effect of multiple stressors in a wild population, and emphasises the importance of assessing the effect of stressors in combination.

• Hansen, Thomas Fredrik; Paulsen, Jonas & Muhidin, Hanna Samir Abukar (2026). Assembly Theory and Biological Selection. A Computational and Conceptual Analysis of Generative Bias. Universitetet i Oslo. Full text in Research Archive
• Sletten, Charlotte; Nelson, Jessica; Nordal, Inger; Wabuyele, Emily; Winden, Veerle Van & Wamaitha, Rose [Show all 11 contributors for this article] (2026). Phylogeny, Taxonomy, and Conservation of the genus Cyrtanthus Aiton (Amaryllidaceae J.St.- Hil) in East Africa. Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract and files will be published: 2028-05-22

• Angell, Thorvald; Eiler, Alexander & Stensrud, Eivind (2026). Changes at the Base of the Food Web in the Oslofjord and Skagerrak. Top predators as food web sentinels using DNA metabarcoding and stable isotope analysis. Universitetet i Oslo. Full text in Research Archive Show summary

  The coastal food webs of the Oslofjord and Skagerrak are undergoing alterations in structure, energy transfer, and basal organic matter (OM) sources due to multiple anthropogenic drivers, including eutrophication, increased terrestrial runoff, and climate change. These interacting pressures elevate the influx of terrestrial OM (tOM) and are associated with an increase in chromophoric dissolved OM (cDOM) to the coastal areas. As these allochthonous inputs increasingly exceed the autochthonous OM production, the resulting brownification alters the light attenuation regimes and thus drives the base of coastal ecosystems towards heterotrophic processes. Despite these documented biogeochemical shifts, the extent to which they disrupt the base of the food web and propagate upward through trophic interactions to the top predators remains poorly understood. Resolving how anthropogenic stressors restructure trophic pathways is also essential for predicting ecosystem responses to conservation and restoration strategies. To investigate how anthropogenic pressures have altered the coastal food web over the last two decades, dietary DNA metabarcoding was conducted on gut content from harbour seal (Phoca vitulina) and great cormorant (Phalacrocorax carbo), targeting secondary consumption with emphasis on the base of the food web. Two complementary gene markers were used: 18s rRNA V4 (Pirreda) to characterize the eukaryotic protist communities and COI (Leray-XT) to identify metazoan prey, including fish and invertebrates. To assess temporal shift in basal energy and organic matter sources, stable isotope analysis of top predator tissue was complemented with longterm monitoring data of Atlantic cod (Gadus morhua) and blue mussel (Mytilus edulis). These multiple approaches successfully characterized the food web from top predators down to the base of the food web. Although the findings revealed diet partitioning in the top predators primary consumption, reflecting different foraging strategies, they exhibit a strong overlap in the lower trophic levels and at the base of the food web. This suggests that the top predators are affected by the same bottom-up regime, rendering them mutually susceptible to the cascading effects of anthropogenic pressures, particularly increased terrestrial organic matter inputs. Finally, complementary isotopic data revealed a significant decrease in d 13C over the past 20 years, signaling a systemic shift in the coastal food web’s primary energy base toward allochthonous carbon sources.

• Wälchli, Sébastien; Inderberg, Else Marit; Progida, Cinzia Anita Maria & Hellesøy, Henrik Tse Zhiong (2026). Pre-clinical Validation of Humanized anti CD37-CAR. Universitetet i Oslo. Full text in Research Archive Show summary

  Chimeric antigen receptor (CAR) T-cell therapies targeting CD37 represent a promising strategy for the treatment of B-cell malignancies and acute myeloid leukemia (AML). However, due to the single-chain variables (scFvs) murine-derived origin, it possesses the risk of immunogenicity, limiting CAR T-cell persistence and efficacy in clinical settings. This study aimed to preclinically validate humanized variants of the HH1 monoclonal antibody derived scFv with the goal of selecting a candidate with reduced immunogenicity while preserving identical functionality to its murine counterpart. The humanized HH1 CAR constructs were cloned, expressed and evaluated using several approaches including in silico modelling, in vitro functional assays, and an in vivo xenograft model. In primary T cells, humanized constructs exhibited comparable CAR expression, expansion, and viability relative to their murine counterpart. Functional assays revealed retained antigen-specific cytotoxicity, cytokine production, and binding avidity. In vivo, selected candidates (hHH1-3 and hHH1-4) demonstrated effective tumor control, with hHH1-3 showing a modest improvement in survival. Collectively, these findings demonstrate that humanization of the HH1 scFv did not compromise CAR T-cell functionality, validating hHH1-4 as the candidate for further clinical development.

• Dalhus, Bjørn; Eide, Lars; Herselth, Hans-Petter & Nygård, Mickael (2026). Understanding the biochemical functions of hBCAT2. Defining the role of dimerization in enzyme activity and allosteric regulation. Universitetet i Oslo. Full text in Research Archive
• Inngjerdingen, Marit & Pasamar, Nicole Camila Lopez (2026). Impact of tumor microenvironment factors on the cytotoxic activity of NK-cell derived extracellular vesicles. Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract and files will be published: 2028-05-15

• Thiede, Bernd & Sargautis, Domantas (2026). LC-MS peptide mapping of monoclonal antibodies, antibody-drug conjugates and host cell protein impurities. Universitetet i Oslo. Full text in Research Archive
• Thoen, Ella; Skrede, Inger; Kauserud, Håvard & Martinez, Glever Alexander Velez (2026). Ericaceous root associations and long-term community responses of Archaeorhizomycetes in boreal forests after clear-cutting. Universitetet i Oslo. Full text in Research Archive Show summary

  Archaeorhizomycetes is a fungal class positioned within Ascomycota, currently comprising only four formally described species. Specimens of the class are extremely difficult to isolate due to their slow-growing nature, frequently outcompeted by fast-growing organisms. The last two species isolated from the roots of Rhododendron species in Japan raised the hypothesis that this group may be associated with plants of the family Ericaceae and brought the possibility of obtaining new isolates. Prior to this, the class contained only two species isolated from coniferous trees in the boreal forests of Europe, where high abundances have been reported using environmental sequencing of soil. In a recent study, Archaeorhizomycetes showed negative long-term responses to clear-cut forestry. In this two-chapter thesis, I first isolated Archaeorhizomycetes cultures, described a new species, and studied their colonization of ericaceous roots. One isolate obtained from the root of Rhododendron degronianum was described as Archaeorhizomyces rhododendri, a newly proposed species. A. rhododendri formed conspicuous hyphal coils inside the rhizodermal cells of Vaccinium myrtillus seedlings and is potentially widely distributed across the Northern hemisphere. One second isolate from R. hirsutum was identified as Archaeorhizomyces sp. strain OMG4201. For this tentatively new species, only DNA sequence data were analyzed, since it did not grow enough to be visualized during the study period. In the second chapter, I investigated the long-term responses of clear-cut forestry on Archaeorhizomycetes and assessed their distribution across the soil profile in twelve boreal forest pairs in Norway, each one comprising a pair of mature previously clear-cut (CC) forest and a non-clear-cut, near natural (NN) stand. Using long-read sequences of the rRNA operon analyzed in a phylogenetic context, I recovered 78 OTUs forming thirteen main clades. The community composition of Archaeorhizomycetes was most strongly structured by soil depth, but also by forestry. Other site-specific conditions, such as climate and vegetation, also impacted the community composition. The species indicator analysis showed that several OTUs had strong affiliation for either organic or mineral soils, while thirteen OTUs and one clade showed affinity for either forestry types (CC or NN). The two approaches in this thesis allowed me to combine culture-dependent methods and long-read metabarcoding to characterize and better understand the diversity of Archaeorhizomycetes, in terms of their association with ericaceous plants, how they are structured in the soil, and how they respond to forestry.

• Kumari, Pooja; Ciosk, Rafal & Rekdal, Tuva Korneliussen (2026). Cold-Induced Cellular Dormancy. Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract and files will be published: 2031-05-15

• supervisor), Kjetil Taskén (Main; (Co-supervisor), Mary-Ann Jallad; (Co-supervisor), Katharina Bischof; supervisor, Fahri Saatcioglu (Internal & Tømte, Mathilde (2026). Exploring novel treatment strategies to overcome resistance in ovarian cancer using high-throughput combination drug screening and patient-derived organoids. Universitetet i Oslo. Full text in Research Archive Show summary

  Tubo-ovarian cancer is the most lethal gynecological cancer, and is likely to remain so, as successful treatment approaches have been established for other gynecological cancers, such as cervical cancer. Most ovarian cancer patients are diagnosed at an advanced stage with highly heterogenous tumors, leading to high rates of treatment resistance and disease recurrence. With limited alternative treatment options, many patients are left without any effective therapy. To address this therapeutic gap, there is a critical need to identify novel treatment strategies with the potential to overcome resistance. In this work, we used high-throughput drug sensitivity screening to explore potential strategies for overcoming resistance in ovarian cancer. We screened a large library of single agents, and their combinations, in a panel of ovarian cancer cell lines chosen to reflect key molecular features and the spectrum of treatment sensitivities observed in patients. The study progressed to a more physiologically relevant disease model using patient-derived organoids in drug sensitivity screening to better mirror the complexity of patient tumors. This exploratory study revealed synergistic drug combinations with potential relevance for overcoming treatment resistance in ovarian cancer and generated a drug response profile in a patient-derived disease model using high-throughput drug sensitivity screening. These findings highlight candidate combinations and model systems that may inform future preclinical and translational research on treatment resistant ovarian cancer.

• Paulsen, Jonas; Rossini, Roberto & Bakir, Anders Rudi Bråthen (2026). Bioinformatics and Computational Science: Modeling Nuclear Shapes from 3D Genome Models. Universitetet i Oslo. Full text in Research Archive Show summary

  Changes in nuclear mechanics and nuclear morphology are linked with severe pathologies such as breast cancer, Emery-Dreifuss muscular dystrophy, and Hutchinson-Gilford progeria syndrome. This thesis investigates a new method in nuclear morphological analysis by evaluating the shape of 3D genome models generated from Hi-C contact data. Can biologically relevant nuclear shapes be estimated from genome models generated from Hi-C data alone? Chrom3D was used to generate 3D genome models. One of the limitations of Chrom3D modeling is that it was designed to use a predefined perfect sphere as a nuclear boundary constraint. Consequently, it does not include functionality to estimate the shape of the 3D genome model and the nucleus. To address this, the method combines ellipsoid fitting and PCA-based analysis of the genomic point cloud. The method was further developed into a Python package called nuclear_shape for reuse. The pipeline was then used to analyze 3D genome models generated with Hi-C data from different cell types with distinct nuclear shapes (fibroblasts vs. B-cells), as well as cells in confinement and breast cancer progression. The results show shape changes across cell types and cell states. Although the changes were small, the directionality was in accordance with the biological outcome. This encourages the view that Hi-C contact data implicitly contains enough geometric information to estimate relative differences in nuclear shape. However, further development and testing are needed to integrate a nuclear shape method with 3D genome modeling. This could provide a deeper understanding of 3D genome organization and the relationship between the shape of the nucleus and the radial positioning of the genome.

• Edvardsen, Bente; Engesmo, Anette; Egge, Elianne; Gran, Sandra & Vågsdal, Sindre (2026). Differences in seasonal variation of protist communities in the outer Oslofjord observed through microscopy and metabarcoding. Universitetet i Oslo. Full text in Research Archive Show summary

  Phytoplankton are used worldwide as an indicator of the health and ecological status of aquatic pelagic ecosystems. The most commonly used method to monitor phytoplankton communities is through microscopy, but with technological advancement new methods are being developed to monitor the environment. One such technology to monitor microbial communities is metabarcoding. This study aimed to compare the protist communities revealed by microscopy to that revealed through metabarcoding. The comparison of metabarcoding and microscopy was done by looking into the relative abundance and relative richness of the most common protist groups, as well as the species and genera with the highest relative abundance within those groups. In addition, all the species and genera found with both methods with a focus on diatoms and dinoflagellates. This was done to examine the overlap in the taxa found with both methods. When looking at overlapping taxa both the richness as well as the differences between the diatom and dinoflagellate genera with highest relative abundance was examined. This comparison was done to samples from two stations across 22 months from February 2023 to November 2024. The samples were collected from the stations “Hvaler” in Ringdalsfjorden, referred to as station R-5, and “Hasslav” located in Haslau, Singlefjorden, referred to as station S-9, in outer Oslofjorden. The metabarcoding analysis targeted the V4-region in the 18S rRNA gene for amplification. When looking at microscopy the relative abundance was calculated using the carbon concentration calculated from the biovolume estimated from microscopy cell counts. The relative abundance of metabarcoding was based on number or reads the different amplicon sequence variants (ASV’s) had. Over the 22 months there were some differences between the two stations with R-5 having a larger relative abundance of Ciliophora and Cryptophyta while S-9 had a larger relative abundance of haptophytes and euglenophytes. These differences may be explained by the difference in physical and chemical conditions between the stations. Station S-9 always has higher light penetration and salinity with salinity being much higher from august 2023 to July 2024. When comparing nutrient concentrations, station R-5 generally had a higher concentration of both nitrogen and silicate. When comparing the relative abundance found with both methods diatoms and Ciliophora were underrepresented in the relative abundance calculated using reads while dinoflagellates and Cryptophyta were overrepresented. When looking into the relative richness found with both methods there were similarities seen with dinoflagellates but major differences between diatoms. This difference likely stems from the difference in richness, where for dinoflagellates metabarcoding displayed higher richness than microscopy, while for diatoms microscopy demonstrated higher richness when compared to metabarcoding. There are observed correlations between the relative abundance calculated with number of reads and the relative abundance calculated with carbon concentration. This is more pronounced when examining specific groups with similar sizes as seen when examining the genera of diatoms and dinoflagellates with the highest overall relative abundance. This correlation lessens when looking at groups of different sizes such as the overall relative abundance of diatoms and dinoflagellates.

• Eikrem, Wenche; Bekkby, Trine & Hansen, Solveig Hakestad (2026). Morfologi og fenologi hos to tangarter, Ascophyllum nodosum og Fucus vesiculosus, ved forskjellig bølgeeksponering på Senja. Universitetet i Oslo. Full text in Research Archive Show summary

  Denne oppgaven har undersøkt forskjellige morfologiske trekk og fenologiske hendelser i tangartene grisetang (Ascophyllum nodosum) og blæretang (Fucus vesiculosus) langs en bølgeeksponeringsgradient, fra veldig beskyttet til moderat eksponert. Det ble funnet at forskjell i bølgeeksponering korrelerer med forskjeller i lengde, bredde og antall blæregenerasjoner for begge arter, og det er i den mest beskyttede lokaliteten at man finner de lengste og eldste individene. For blæretang var eksponeringsgrad assosiert med forskjeller i antall blærer per blærepar. Dette dreier seg trolig om hvilken variant av blæretang som er vanligst å finne ved forskjellige eksponeringsgrader. Blærene i begge arter øker i størrelse med økt talluslengde, og vokser på en koordinert måte i samtlige dimensjoner. Blærestørrelse i grisetang varierer langs eksponeringsgradienten, men her er det den middels eksponerte lokaliteten som har størst blærer, mens den mest beskyttede har minst og den mest eksponerte havner i midten, når talluslengde er tatt høyde for. Blæredannelse skjer hovedsakelig i mai for begge arter, men i grisetang var den mest beskyttede lokaliteten én måned tidligere ute. Reseptaklene utvikler seg etter samme mønster i lengde og bredde, mens tykkelsen øker først utover i sesongen når reseptaklene modnes. Størrelsen på reseptaklene vokser ikke med algens talluslengde. Det ble funnet noe formvariasjon langs eksponeringsgradienten for begge arter. Det ble ikke funnet noen forskjell i tidspunkt for reseptakkeldannelse mellom lokalitetene, men gametedannelse i grisetang inntraff tidligere i den mest beskyttede lokaliteten sammenlignet med de andre, og gametedannelsen i blæretang inntraff tidligst i den intermediært eksponerte lokaliteten, deretter i den mest beskyttede lokaliteten, og til sist i den mest eksponerte. Vekst i grisetang var lavere på den mest eksponerte lokaliteten sammenlignet med de andre, men dette kan ha flere mulige årsaker utover bølgeeksponering. Vekst i blæretang varierte ikke med bølgeeksponering. Vekstraten er høyest på sommeren og lavest under mørketida på vinteren. Kjønnsfordelingen var lik 1:1 for begge arter. Det ble også funnet at man enkelt kan se om både grisetang og blæretang har begynt å danne gameter - omtrent med én gang reseptaklene har begynt å blåse seg opp og tykkelsen øker, er sannsynligheten for å finne gameter høy.

• Kauserud, Håvard; Skrede, Inger; Maurice, Sundy; Ronold, Eivind Kverme & Heijden, Sven Jorrit van der (2026). ‘Plugging’ into the lignocellulose matrix: Revealing long-term effects of clear-cut forestry on deadwood-associated fungi and decomposition using wooden plugs. Universitetet i Oslo. Full text in Research Archive Show summary

  Boreal forests form important carbon sinks, but increasing disturbances such as forestry could alter carbon retention time in these ecosystems by affecting the decomposition rate of litter and deadwood. As fungi are the primary decomposers of deadwood in boreal forests, studying changes in their community structure and decay activity are key for understanding how disturbances affect decomposition. In this thesis, I aimed to identify how changes in forest environments after regeneration from a single round of clear-cutting affected wood-associated fungal communities, and to link this to decomposition of Norway spruce (Picea abies). For this purpose I conducted an experimental decomposition study across 10 study sites in South-east Norway, where each site included one mature previously clear-cut (CC) forest plot and a nearby near-natural (NN) forest plot. In each study plot, 20 deadwood logs were inoculated with a standardized wooden plug and left to decompose for 3 years. After retrieval, mass loss was measured from the plugs and DNA metabarcoding was performed on sawdust samples of both plugs and host logs, targeting the fungal ITS2 sequence. The plugs captured the majority of fungi in the logs and the community composition clearly reflected the decay stage of the host logs. No differences in taxonomic diversity were found between forest types, but communities differed compositionally. In the early decay stages, plugs from CC plots lost less mass than those from NN plots and held higher proportions of soft rot fungi. Oppositely, in the later decay stages, the plugs from CC plots decomposed faster than in NN plots, which was coupled to higher proportions of white rot fungi. Community differences between forest types were linked to abundance and diversity of deadwood substrates. The observed shift in community structure and altered decomposition patterns in mature clear-cut forests could affect carbon fluxes in boreal forests. Using wooden plugs to bait wood-saprotrophic fungi showed to be a promising approach to study deadwood ecology and opens up possibilities for future studies, which are needed to deepen our understanding of how forest management affects fungal communities and ecosystem functions.

• Grallert, Beáta; Langiu, Mélanie; Hersleth, Hans-Petter & Hagen, Alma Mei (2026). General Control Nonderepressible 2 in Mitotic Regulation. Universitetet i Oslo. Full text in Research Archive Show summary

  Faithful cell division is essential for maintaining genome integrity and preventing tumorigenesis. Recent work from our group identified a novel regulatory axis controlling mitotic fidelity, centered on the regulation of protein phosphatase 1 isoforms alpha and gamma (PP1α and PP1γ) by the kinase general control nonderepressible 2 (GCN2) during early mitosis. Notably, cancer cells exhibit a pronounced dependence on GCN2 for mitotic progression compared to non-transformed cells. In addition, GCN2, traditionally associated with cellular stress responses, appears to be activated in a cell cycle-dependent manner in unstressed cells, although the underlying mechanism remains unclear. This study aimed to investigate the mechanism of mitotic GCN2 activation and to establish a platform for monitoring the GCN2-PP1 interaction in live cells. To address the first aim, the potential involvement of the ribosome-associated protein GCN1, and the role of CDK-dependent phosphorylation of the ribosomal protein uL11/RPL12 were investigated. Our results suggest that mitotic activation of GCN2 occurs independently of GCN1. In parallel, cancer cell lines expressing mutant variants of RPL12 were generated to facilitate further studies of ribosome-associated regulation of GCN2. To support analysis of the GCN2-PP1 interaction, structural modelling and molecular cloning approaches were employed to develop a live-cell interaction assay. Together, the tools and findings generated in this study provide a foundation for further investigation of cell cycle-dependent GCN2 activation and may inform future strategies to target GCN2 in cancer.

• supervisor:, Main; Arild, First name:; Johnsen, Last name:; -------------------------------; 1:, Co-supervisor & Kristin, First name: [Show all 13 contributors for this article] (2026). Main title: Annual and individual variation of blood parasites in bluethroats. Universitetet i Oslo. Full text in Research Archive Show summary

  Parasites are common in all animal groups and can reduce host health and fitness. Birds are often infected by blood parasites (haemosporidians) of the genera Plasmodium, Leucocytozoon and Haemoproteus. They are transmitted by biting insects and can cause acute and chronic infections. In this thesis, I used long-term data (1991-2025) from bluethroats (Luscinia svecica svecica) breeding in a subalpine valley in Norway to study population- and individual-level patterns of haemosporidian infection. Leucocytozoon and Haemoproteus infection status were detected with a multiplex polymerase chain reaction, and their estimate of infection intensity (relative quantity) was determined from gel band strength. Plasmodium infection status and estimate of infection intensity were quantified with quantitative PCR. Firstly, I examined how prevalence and relative quantity varied annually and tested whether this was related to local breeding density and temperature. I then analysed if individual-level traits such as sex, age, morphology (body mass, wing length, tarsus length), plumage traits (female score, male red border) and MHC class II traits (PSS allele count, distance to optimum) were related with infection. Finally, I tested for associations between reproductive traits (egg laying date, clutch size) and infection status. Haemosporidian prevalence and relative quantity showed annual variation, but this was only marginally positively related to temperature and not breeding density. This suggests that conditions along migration routes and wintering areas are more important. At the individual-level, total infection status increased with age, and males had higher relative quantity than females. Furthermore, males with longer wings, longer tarsi and larger red borders had a higher infection status or relative quantity. MHCII variables showed no clear relationship with relative quantity. Finally, infections did not have detectable associations with reproductive traits. Overall, haemosporidian infections in this wild population are common and highly diverse through time, shaped more by host traits and large-scale processes than by local environmental factors, and their effects on reproductive traits appear subtle.

• Mysterud, Atle; Rivrud, Inger Maren; Meisingset, Erling; Unsgård, Even & Prøven, Jakob Utvær (2026). Non-lethal effects of hunting on red deer (Cervus elaphus). Movement responses and habitat use during the hunting season. Universitetet i Oslo. Full text in Research Archive Show summary

  Human hunting is a widespread disturbance in many wildlife systems, and research has traditionally focused on its direct lethal effects on population dynamics. However, hunting may also induce non-lethal behavioral responses, as prey animals alter movement behavior and habitat use in response to perceived predation risk. Such responses may create a human-induced landscape of fear, where animals balance resource acquisition against safety. This thesis investigates how hunting influences movement behavior and habitat use in red deer (Cervus elaphus) in Lærdal, Norway. Using GPS data from 48 red deer collected between 2017 and 2025, I examined behavioral responses to hunting in relation to sex, light conditions, and day class (weekend vs. weekday). Based on theory related to predation risk and landscape of fear, and the expectation that infield habitats and periods of high human activity increase perceived risk, I predicted that red deer would increase movement rates and reduce use of open infield habitats during the hunting season, particularly during daylight and weekends. Results showed that step length exhibited strong non-linear seasonal patterns, with a pronounced increase in male movement that corresponded closely with the expected peak in rutting activity. Although hunting season had a statistically significant effect on step length, the overall magnitude of the effect was modest. This suggests that rutting behavior, rather than hunting activity alone, was the primary driver of seasonal movement patterns. In comparison, red deer showed clearer and more consistent changes in habitat use in response to hunting. Red deer reduced their use of infield habitats during the hunting season, particularly under daylight and twilight conditions, indicating a shift towards safer habitats under increased perceived risk. These effects were more pronounced in males than in females. Overall, the results indicate that hunting primarily influences when and where red deer move, rather than substantially altering overall movement rates. The findings support the concept of humans shaping a landscape of fear and demonstrate the non-lethal impacts of hunting on wildlife behavior.

• Leithe, Edward; Kryeziu, Kushtrim; Lothe, Ragnhild Adelheid & Grønning, Anna (2026). Functional characterization of short linear motifs involved in the endocytosis and degradation of the gap junction channel protein connexin43. Universitetet i Oslo. Full text in Research Archive
• Jacobsen, Johanne Tracey; Patrinos, Corentin Le Saos; Johansen, Finn-Eirik & Thanh, Celina Nha-Mi Le (2026). From Innate Immune Activation to Germinal Center Outputs: A Systematic Profiling of TLR agonists and Vaccine Vehicles. Universitetet i Oslo. Full text in Research Archive Show summary

  Abstract Long-lasting vaccine protection depends on the ability of the immune system to generate high-quality antibody responses. This process occurs within germinal centers (GCs), specialized microenvironments where B cells undergo selection and maturation to form long- lived plasma cells and memory B cells. While the antigen is the primary component of a vaccine, it is often not very immunogenic on its own to induce a strong immune response. Therefore, the resulting immune response is shaped by additional components, particularly adjuvants and delivery vehicles. These elements influence early innate immune signals and thereby affect how the adaptive response is initiated and develops. In this study, the effects of different TLR agonists and vaccine delivery vehicles on GC responses were investigated by analyzing immune responses in the draining popliteal lymph node following immunization with NP-OVA combined with the respective adjuvants or vehicles. The study aimed to determine how early innate activation shapes downstream adaptive immunity and the results demonstrate that both TLR agonists and vaccine vehicle formulations shape GC responses in distinct ways. Characterizing these differences is important for improving vaccine design, as it provides a framework for understanding how early immune signals influence the quality and durability of antibody responses. Ultimately, this may contribute to the development of more effective vaccines in the future.

• Edvardsen, Bente; Egge, Elianne; Engesmo, Anette; Stadniczenko, Sandra Gran & Sævik, Olea Smoge (2026). Protistsamfunnets sammensetning og sesongvariasjon i forhold til miljøforhold i Ytre Oslofjord. Universitetet i Oslo. Full text in Research Archive Show summary

  Oslofjorden er et kystøkosystem som allerede er sterkt påvirket av menneskelig aktivitet, blant annet gjennom tilførsel av næringsstoffer fra landbruk og avløp. I et varmere og våtere klima forventes mer nedbør og avrenning, som øker tilførselen av ferskvann, næringssalter og oppløst organisk materiale. Dette kan endre både saltholdighet, lysforhold og næringssituasjon i vannsøylen, og dermed påvirke protistsamfunn som responderer raskt på slike endringer. For å belyse disse påvirkningene undersøkes hvordan protistsamfunnene varierer i tid og rom langs et transekt fra den mer ferskvannspåvirkede og lysbegrensede Iddefjorden til mer marine, lysrike stasjoner ved Hvaler. Vannprøver ble samlet inn i 2023–2024 og analysert med metastrekkoding av V4‐regionen i 18S rRNA‐genet. Protistsamfunnene ble deretter satt i sammenheng med samtidige målinger av fysiske, kjemiske og biologiske variabler. Resultatene viser at protistsamfunnene varierte både langs transektet og gjennom året, med tydelige sesongmønstre. Ved de ytre, mer marine stasjonene dominerte dinoflagellater, Syndiniales (parasittiske protister) og kiselalger, mens de ferskvannspåvirkede indre stasjonene hadde større innslag av svelgflagellater, grønnalger, flimmerdyr og Perkinsea (parasittiske protister). Alfadiversiteten (indekser for rikhet og jevnhet) var lavest sommeren 2023 og høyest om høst og vinter. Betadiversiteten var størst mellom årstider, men ordinasjonsanalyser viste også et tydelig skille mellom indre og ytre stasjoner innen samme årstid. Vår og sommer hadde et høyere innslag av fototrofe grupper, som kiselalger, dinoflagellater og svelgflagellater, i motsetning til høst og vinter hvor heterotrofe og parasittiske grupper dominerte, særlig Syndiniales. På tvers av sesonger fremstod lavere saltholdighet og høyere fDOM (fluorescerende oppløst organisk materiale) og nitrogen‐tilgjengelighet som de miljøvariablene som best skilte de indre fra de ytre stasjonene. De indre stasjonene var kjennetegnet av flere brakkvannstilknyttede grupper som svelgflagellater og grønnalger, mens de ytre stasjonene hadde høyere andeler kiselalger og dinoflagellater. Dette tyder på et relativt stabilt, brakkvannspåvirket preg i indre del av transektet, med jevn tilførsel av organisk materiale gjennom året, i kontrast til tydeligere årssykluser og markerte sesongskifter ved de ytre stasjonene. Metastrekkoding gir et detaljert bilde av protistsamfunnene ved å fange opp små og morfologisk like organismer som ofte overses i mikroskopi. Til tross for noe ujevn prøvetaking tyder resultatene på at kombinasjoner av ferskvannstilførsel, lyssvekking og næringstilførsel er sentrale pådrivere for variasjonen i protistsamfunn langs transektet, og gir et innblikk i hvordan pågående og fremtidige klimaendringer kan påvirke struktur og funksjon i kystnære planktonsamfunn.

• Eidesen, Pernille Bronken; Gregers, Tone Fredsvik & Waltila, Aleksandra Milene Johnsen (2026). Virtuelle feltguider som verktøy for å gjøre overgangen mellom teori og feltferdigheter i biologi mer forståelig. Universitetet i Oslo. Full text in Research Archive Show summary

  I denne masteroppgaven undersøkes det om virtuelle feltguider (VFG) som et verktøy i undervisning kan fungere som et mer effektivt bindeledd mellom klasseromsteori og praktisk arbeid knyttet til felt, enn hva mer tradisjonelle representasjonsformer som bilder og tegninger gjør i dag. VFGene som oppgaven bygger på ble laget i forbindelse med FieldPass prosjektet til Universitetssenteret på Svalbard (UNIS), og viser 360°-bilder fra ulike lokasjoner på Svalbard, sammen med relevant informasjon knyttet til biotiske og abiotiske variabler som karakteriserer de ulike lokasjonene. Gjennom et forskningsdesign bestående av mixed-methodes og triangulering har studenter på to emner ved UNIS gjennomført feltarbeid og casestudie med og uten VFG som verktøy. Det ble gjort observasjoner av undervisning, og i etterkant ble det gjennomført spørreskjema og intervju som er analysert gjennom innholdsanalyse og deskriptiv statistikk. Funnene viser at studenter føler seg mer forberedt når de bruker VFG som et forberedelsesverktøy, og at oppgaven de blir gitt med VFG på forhånd ikke trenger å være avansert for at de skal få et positivt utbytte av å bruke den. De VFGene som hadde sesongvariasjon ga dem en bedre forståelse av landskapet, og de kom raskere i gang med oppgaver. I arbeid med casestudie syntes studentene at oppgaven ble mer virkelighetsnær ved å bruke VFG, og at den i tillegg ble lettere å løse med å bruke dette verktøyet, samtidig som de fikk øvd på å bruke ferdigheter de hadde lært ute på feltlokasjoner. Ut ifra oppgaven konkluderes det med at VFG kan minke den kognitive belastningen for studenter som skal ut i nye områder, noe som gjør at de raskere kommer i gang og får et større utbytte av felt. Det konkluderes også med at bruken av VFG i oppsummeringsoppgaver gjør at studenter får trent bedre på ferdigheter og teori lært i felt.

• Økstad, Ole Andreas Løchen; Simm, Roger & Oksvold, Maria Valente (2026). PilZ as a regulator of type IV pilus formation and virulence in Acinetobacter baumannii. Universitetet i Oslo. Full text in Research Archive Show summary

  Acinetobacter baumannii is an opportunistic multidrug-resistant pathogen and a major cause of hospital-acquired infections worldwide. Several virulence-associated traits contribute to its persistence and pathogenicity, including biofilm formation, surface colonization, and motility. In many bacteria, these processes are regulated by the second messenger cyclic di-GMP (c-di-GMP), a global messenger molecule involved in regulating the transition between motile and sessile lifestyles. PilZ domain-containing proteins are among the best-characterized c-di-GMP effector proteins and have previously been implicated in regulation of type IV pili (TFP) assembly and function in several bacterial species. However, in A. baumannii PilZ differs structurally from previously characterized c-di-GMP-binding PilZ proteins, making its biological role less clear. To investigate the role and function of PilZ in A. baumannii, phenotypic analyses were performed using pilZ transposon insertion mutants, pilZ complementation strains, and pilZ overexpression strains. Twitching motility, biofilm formation, antimicrobial susceptibility, and gene expression were assessed. In addition, transmission electron microscopy, comparative proteomics, whole-genome sequencing, and bioinformatic analyses were used to further investigate molecular and cellular structural effects associated with the pilZ mutation. pilZ mutation resulted in strongly reduced twitching motility and loss of TFP-like surface appendages, supporting a possible role for PilZ in TFP-associated phenotypes. TFP-like structures were observed following complementation despite failure to restore twitching motility, suggesting that restoration of pili assembly alone may not be sufficient to regain functional TFP-mediated motility. This was further supported by comparative proteomic analyses identifying altered abundance of several proteins involved in TFP function following pilZ mutation and overexpression. In contrast, the pilZ mutation had limited effects on biofilm formation (biofilm biomass) under the experimental conditions used in this study, while findings related to aminoglycoside susceptibility remained less conclusive, and could potentially be explained by secondary mutations identified in the transposon insertion mutants by whole-genome sequencing. Altogether, the findings of this study support a possible role for PilZ in TFP-associated phenotypes in A. baumannii and suggest that balanced pilZ expression is required for proper TFP function.

• Eiler, Alexander; Riis-Pedersen, Christine; Hessen, Dag Olav & Minde, August Woldseth (2026). Under ice: The methane cycle in meromictic lakes during winter. Universitetet i Oslo. Full text in Research Archive Show summary

  Anthropogenic pressures and climate warming are increasingly driving freshwater ecosystems toward permanent stratification, yet the implications for the global carbon cycle remain poorly constrained. Meromictic lakes act as substantial reservoirs for dissolved greenhouse gases in their anoxic monimolimnia, but the efficiency of the chemocline in attenuating upward-diffusing methane (CH4) during winter ice- cover requires quantification. This study investigates depth-resolved CH4 and carbon dioxide (CO2) concentrations, alongside stable carbon isotope (δ13C) profiles, in two contrasting boreal meromictic lakes (euxinic Pollevannet and ferruginous Oppsjø) under winter conditions. High-resolution profiling revealed massive deep-water gas accumulation, with monimolimnetic CH4 concentrations exceeding 106 nM in both systems. In Pollevannet, δ13C − CH4 profiles exhibited a sharp 20‰ depletion across a 2-meter interval at the chemocline, providing isotopic evidence of a highly efficient microbial methane oxidation barrier. Furthermore, biogeochemical profiles suggest this barrier is reinforced by cryptic metabolic coupling; anoxygenic phototrophy at the low-light euxinic boundary likely regenerates sulfate (SO2−4 ), potentially subsidizing anaerobic methane oxidation in the underlying water. Oppsjø displayed a broader transition zone with more gradual isotopic shifts, reflecting its distinct ferruginous redox architecture. These findings demonstrate that stable winter stratification sustains a rigid, interdependent microbial bio-filter that effectively sequesters carbon in deep waters and decouples benthic methanogenesis from surface emissions.

• Ergon, Torbjørn Håkan; Storvik, Geir Olve; Helberg, Morten & Schonhowd, Linus Gundelsby (2026). A continuous-time capture-recapture analysis of three gull species in the inner Oslo fjord. Universitetet i Oslo. Full text in Research Archive Show summary

  The continued declines in avian populations are cause for significant concern. In Norway, the black-headed gull (Chroicocephalus ridibundus) along with several other species, such as the European herring gull (Larus argentatus), are in various degrees of decline, and the former being especially threatened, as it is currently registered as critically endangered (CR) on the Norwegian red list. It is therefore crucial to develop the appropriate statistical models to study these declining populations, to inform future conservation efforts, and to ensure appropriate evaluation of the species’ current and future status. This study aims to develop a continuous-time capture-mark-recapture model for estimating mortality hazard rates as a function of age, year, season and climate, as well as providing a measure of between-species synchrony. Furthermore, the study aims to apply this model to a 15-year capture-mark-recapture dataset of gulls originating in the inner Oslo fjord, to estimate survival and synchrony for the black-headed gull, the European herring gull, and the great black-backed gull (Larus marinus). The study found clear patterns of mortality varying with age, with younger individuals experiencing higher risk of death than older individuals. Mortality was substantially higher during winter for all three species, and the model detected a significant effect of the winter North Atlantic Oscillation (wNAO) index on survival, suggesting weather conditions during the wintering period may be an important determinant for survival, especially in early years of life. The mortality rate also had a lesser peak during the breeding period. A high degree of synchrony between species in residual annual mortality rates were also detected. This is indicative of annual variation being driven mainly by large-scale environmental factors, such as climatic conditions and food availability. A rising trend in mortality across years signals worsening conditions for all three species. The black-headed gull, which of the three species is the one most at risk of extinction, had the lowest median mortality of the three, but also displayed the largest wNAO response, as well as the largest annual variation in mortality. This suggests the declines iin the populations of black-headed gulls may be caused by a high sensitivity to unstable environmental conditions, likely in combination with low reproductive output. Both local and broad-scale stressors must therefore be addressed to save the remaining population of black-headed gulls in the Oslo fjord.

• Rességuier, Julien; Falck, Martin & Hansen, Hedda Synnøve (2026). Investigating the ontogeny of branchial cavity lymphoid architecture in zebrafish (Danio rerio). Universitetet i Oslo. Full text in Research Archive
• Grødem, Sverre; Fyhn, Marianne & Lønø, Mads (2026). Spatial and Cell-Local Mechanisms of Perineuronal Net Remodelling in Adult Visual Cortex. Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract and files will be published: 2027-05-15

• Stedje, Prof. Brita; Ortiz, Miguel; Nelson, Jessica; Itambo, Malombe; Hauser, Duncan & Kioko, Joan Mawia [Show all 11 contributors for this article] (2026). A phylogentic study of Dyschoriste (Acanthaceae) with emphasis on mainland Africa. Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract and files will be published: 2028-05-28

• Corthay, Alexandre; Øynebråten, Inger; Johansen, Finn-Eirik & Gjøvaag, Ragnhild Amalie (2026). Enhancing Macrophage Tumoricidal Activity in an Immunosuppressive Tumor Microenvironment. Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract and files will be published: 2031-06-02

• Syljuåsen, Randi; Mariampillai, Adrian Eek; Rein, Idun Dale; Falnes, Pål & Finnsdatter, Marte (2026). Optimization of spectral flow cytometry for multi-analysis of DNA damage signaling pathways after proton irradiation. Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract and files will be published: 2027-05-15

• Butenko, Melinka A.; Lalun, Vilde O. & Mansika, Maren (2026). Investigating the functional significance of length variation in the Q-tract in the Arabidopsis thaliana transcription factor LRP1. Universitetet i Oslo. Full text in Research Archive Show summary

  Plants are sessile organisms that must adapt to fluctuating environments. Roots are important for nutrient and water uptake, and thus growth of the entire plant. Genetic variation is essential for modulating adaptive capacity of an organism, and in plants, for example, genetic polymorphism contributes to variation in root system architecture. Genomic regions containing short tandem repeats often show length variability in populations, and they have been shown to affect gene expression and protein function. Their rapid mutation rate, compared to single nucleotide polymorphisms, and studies showing correlation between repeat lengths and local environmental niches, suggests that they are important for driving adaptive phenotypic traits. The Arabidopsis thaliana transcription factor LATERAL ROOT PRIMORDIUM1 (LRP1) contains a glutamine (Q)-tract that varies in length across ecotypes (accessions) from 4 to 12 Qs. LRP1 functions in lateral root development and is induced by auxin. Overexpressing LRP1 has previously been shown to affect primary root length and lateral root density compared to wild-type. This study sought to further investigate the functional significance of LRP1 and its Q-tract in root development under control and stress exposed growth conditions. By transiently expressing LRP1-GFP fusion proteins in leaves of Nicotiana benthamiana, we investigated the subcellular localization of LRP1. LRP1 localized in the nucleus, and the localization was not affected by absence, or length variation of the Q-tract. Root phenotypes of loss-of-function lrp1 mutants in Arabidopsis thaliana grown under control and stress conditions were analyzed to assess the functional significance of LRP1 in root development under control and stress induced conditions. Arabidopsis thaliana lines overexpressing LRP1 with different Q-tract lengths were used to examine the effect of the Q-tract on root length and branching under control conditions as well as under stress. Finally, root phenotypes of several accessions representing the natural variation in Q-tract length were compared under the same control and stress conditions as the overexpression lines with the aim of dissecting the effect of the Q-tract to other genetic variability. Our results indicate that LRP1 has a limited and redundant role in root development and stress response. However, LRP1 Q-tract length variations do appear to result in phenotypic differences when overexpressed.

• Leithe, Edward; Lothe, Ragnhild Adelheid & Arnesen, Karen Irene (2026). New insights into the role of ubiquitination in the regulation of Connexin43-based gap junctions. Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract will be published: 2031-05-21

• Borg, Nora Helene Hammersten; Komisarczuk, Anna Zofia; Falnes, Pål & Haapaniemi, Emma Maria (2026). Development of a Multimodal Screening Platform for Comparative Evaluation of Prime Editing Efficiency. Establishing an experimental framework through reporter cell line generation, prime editing vector construction, and detection assay development. Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract will be published: 2027-05-19

• Santos, Adriana Lopes dos; Supraha, Luka; Gérikas, Catherine & Fladberg, Cornelia Remme (2026). High-Throughput Growth Experiments on Temperature and Salinity Stress in Green Microalgae: Evidence of Diversification and Niche Partitioning in Chlamydomonas and Micromonas. Universitetet i Oslo. Full text in Research Archive
• Lepperød, Mikkel; Haug, Nicolai; Pettersen, Markus; Fyhn, Marianne & Willumsen, Janita Ovidie Sandtrøen (2026). Modelling Grid Cell Symmetry in Complex Geometries. Universitetet i Oslo. Full text in Research Archive Show summary

  Grid cells in the medial entorhinal cortex are widely considered to provide a spatial metric. While computational models often assume they generate a rigid hexagonal pattern uniformly spanning the environment, biological recordings reveal systematic distortions and fragmentation in complex spaces with physical obstacles. This thesis investigates whether a normative model using a geodesic, rather than Euclidean, metric can account for these boundary-induced distortions. We implemented a recurrent neural network (RNN) optimised to preserve local distances under biological capacity limits, trained to perform path integration via velocity inputs across various 2D environments. Initial open-field validation demonstrated that the geodesic model successfully recovers grid-like and band-like representations with distributions comparable to the Euclidean baseline. In complex, multi-compartment environments, the divergent behaviour of the two models became apparent. Unlike the Euclidean baseline, which remained indifferent to internal boundaries, the geodesic model respected them, exhibiting elongated firing fields aligned with walls. Furthermore, in hairpin mazes, the geodesic model successfully captured the structural fragmentation observed in vivo, completely fracturing its global hexagonal lattice (median grid score 0.04) to generate evenly spaced firing fields within individual corridors. Finally, evaluation revealed these emergent representations are highly sensitive to geodesic approximation resolution and training trajectory complexity. Collectively, these findings demonstrate that boundary-induced grid cell distortions can emerge purely as an optimal conformal mapping in RNNs trained on path integration when constrained by environmental connectivity.

• Titelman, Josefin; Heuschele, Jan; Nyeggen, Margot Ulfsdatter & Jønland, Hanna Gisholt (2026). Appendicularia dynamics in the Oslofjord assessed through in situ imaging. Universitetet i Oslo. Full text in Research Archive
• Dinh, Khuong Van; Søreide, Janne Eriksen & Øien, Ingrid (2026). Reproductive Effects of Warming and Plastic Particles on Two Key Arctic Copepod Species. Universitetet i Oslo. Full text in Research Archive Show summary

  The Arctic is warming almost four times faster than the global average, threatening Arctic marine ecosystems. In addition, plastic debris of all sizes are deposited in the marine environment which may put extra stressors on marine species. In the highly seasonal marine Arctic environment, the two copepod species Calanus glacialis and Calanus hyperboreus constitute the key link between primary producers and higher trophic levels. Negative or positive impacts on their populations will therefore propagate throughout the entire Arctic marine food chain. The aim of this study was to investigate reproductive effects of the combined stressors of ocean warming and plastic pollution, and to explore the potential of transgenerational transfer of nanoplastics. To study this, two separate experiments were conducted during the natural spawning period of each species, studying C. glacialis and C. hyperboreus egg and fecal pellet production at two different temperatures in situ (0°C) and warm (4° or 5°C) when 1) starved (control), 2) fed non-limited algae concentrations and 3) fed non-limited algae concentrations contaminated with micro- or nanoplastics. In the six-week C. glacialis experiment, females were fed high concentrations of 30µm microplastic particles, while females in the nine-week C. hyperboreus experiment were fed moderate concentrations of 500 nm fluorescent nanoplastics, which adhered to their algal feed. Temperature was determined to be the dominant driver of altered reproduction and egestion in both species. Plastics effects were weaker but showed stress responses. The study revealed no strong overall interactive effects between temperature and plastic stressors, but indicated some non-additive effects, and strongly suggested generational transfer of nanoplastics in C. hyperboreus. Overall, these results indicate that ocean warming is likely to alter reproductive success in Arctic Calanus species and that micro- and nanoplastics likely act as additional stressors. Given Calanus’ key position in the Arctic ecosystems, reduction in their standing stocks will cause negative cascading ecological and biogeochemical effects.

• Dinh, Khuong Van; Borgå, Katrine & Solgaard, Tuva Flem (2026). Effects of Multiple Stressors on Coastal Copepods: Influence of Copper and PFOS on Thermal Tolerance. Universitetet i Oslo. Full text in Research Archive Show summary

  Ongoing climate warming and chemical pollution are altering marine ecosystems. Copepods are key components of marine food webs, transferring energy from primary producers to higher trophic levels, and may be vulnerable when temperatures exceed their thermal thresholds. Concurrently, increasing anthropogenic activities is expected to enhance exposure to pollutants that may exert toxic effects. In natural environments, multiple stressors act simultaneously and may modify each other’s effects. This study examined how copper and perfluorooctane sulfonate (PFOS) influence the thermal tolerance in Calanus spp. Interactive effects of contaminants and temperatures on survival and sublethal responses assessed as DNA-damage were investigated. Calanus spp. were exposed to five temperatures (8-20 ºC) representative of Oslofjord conditions, as well as either copper (0, 0.5, 1.5, 5 µg/L) for 9 days or PFOS (0, 125, 250, 500, 1000 µg/L) for 10 days. Contaminant concentrations were chosen from preliminary range-finding tests, whereas PFOS concentrations exceeded those typically found in the environment. In both experiments, survival declined with increasing temperature, and a possible thermal threshold was identified between 17 and 20 ºC. Copper had no statistically significant effect on survival (p>0.05). Survival generally decreased linearly with heat accumulation; cumulative temperature did not significantly affect the observed mortality at 5 µg Cu/L. DNA-damage increased with copper concentration and decreased with increasing temperature. In contrast, PFOS had a statistically significant effect on survival and showed an antagonistic interaction with temperature (negative cox regression coefficient). PFOS did not increase DNA-damage at 8 ºC, but did so at 11 and 14 ºC. These findings highlight the need for further research and underscore the importance of considering multiple, co-occurring stressors when assessing the vulnerability of marine organisms to environmental change.

• Kryeziu, Kushtrim; Leithe, Edward; Lothe, Ragnhild A. & Strømnes, Nora Skjerven (2026). Targeting drug resistance of BRAF-mutated colorectal cancer models with novel combination therapies. Universitetet i Oslo. Full text in Research Archive Show summary

  BRAFV600E-mutated metastatic colorectal cancer (CRC) is associated with poor prognosis. Combined inhibition of BRAF and EGFR has improved clinical outcomes, yet resistance remains a major challenge. The aim of this study was to investigate mechanisms of treatment response and resistance in BRAFV600E-mutated CRC models using patient-derived organoids (PDOs) and cell lines with differential sensitivity to BRAF inhibition. PDOs selected for their distinct gene mutations were treated with BRAF and EGFR inhibitors, with or without chemotherapy, and analysed using cell viability assays and molecular analysis. In parallel, the HT-29 and EGFR/BRAF-inhibitor resistant HT-29AE cell lines were used to explore adaptive resistance mechanisms and evaluate alternative therapeutic strategies, targeting PI3K/EGFR, SRC, and RAS proteins. Combined BRAF and EGFR inhibition reduced viability more effectively than single-agent treatments across all BRAF-mutated PDOs, but responses varied significantly among models. The strongest response was observed in the PDO with an additional RNF43-mutation, supporting its role as a potential predictive biomarker. Addition of chemotherapy to the BRAF and EGFR inhibition did not provide a clear benefit in the PDO models. In HT-29 cells, combination treatment suppressed MAPK signalling, whereas HT-29AE cells maintained pathway activity, likely due to acquired NRAS mutation and adaptive signalling. Among alternative combinatorial strategies with BRAF inhibition, pan-RAS inhibition, particularly with daraxonrasib, demonstrated promising effects in overcoming resistance, while SRC inhibition showed limited or antagonistic effects. In conclusion, these findings highlight the importance of tumour-specific genetic context and adaptive signalling mechanisms in determining response to targeted therapy. Targeting upstream RAS signalling represents a promising strategy to overcome EGFR/BRAF inhibitor resistance in BRAFV600E-mutated CRC.

• Eskeland, Ragnhild; Aasland, Rein & Palú, Lucía (2026). Characterisation of known and unknown targets in Rhabdomyosarcoma cell lines. Universitetet i Oslo. Full text in Research Archive Show summary

  Rhabdomyosarcoma (RMS) is one of the most common soft tissue sarcomas in children. RMS is divided in two main subtypes, embryonal (eRMS) and alveolar (aRMS), which differ in their molecular features and clinical behaviour. This divergence poses challenges for the development of effective therapies. Transcription factors (TFs) are key regulators of gene expression controlling cellular programs, and the deregulation of most TFs implies abnormal cellular functions. Throughout the course of this project, different regulatory factors were analysed to investigate their involvement in RMS, building a molecular profile of multiple RMS cell lines. We also set up different cellular assays for characterisation of RMS cell lines including spheroid models. Taken together, these findings will contribute to the characterization of regulatory mechanisms involved in aRMS and eRMS.

• Fenn, José Cerca, Mark Ravinet, Erik Sandertun Røed, Jonathan & Salazar, Diego (2026). How many samples do we need for GWAS? A population simulation approach. Universitetet i Oslo. Full text in Research Archive Show summary

  Understanding the genetic basis of phenotypes is a central goal of evolutionary biology. However, this remains challenging because many traits are likely polygenic and consist of many genes of small phenotypic effects, and it is often difficult to disentangle environmental and genetic influences. Genome-wide association studies (GWAS) are a widely used approach in both human genetics and evolutionary biology research to map genotypes and phenotypes. Nevertheless, determining an appropriate sample size remains a central challenge, as researchers must balance sequencing costs with the need for sufficient sampling power to accurately identify the genetic basis of traits. The goal of this thesis is to understand how the genetic architecture of a trait and the population’s evolutionary history influence the number of samples required to detect causal genetic variants. Using simulations of GWAS under scenario A, we show that statistical power depends on the genetic architecture of the trait (number and distribution of causal loci). Under scenario B, we find that population structure can substantially increase false positives, even on chromosomes without causal SNPs. Finally, we provide a list of recommended sample sizes for each scenario.

• Skarpaas, Olav; Bratli, Harald; Roos, Ruben Erik; Løkken, Jørn Olav & Rennemo, Martin (2026). Prevalence of Phedimus spurius in open shallow calcareous ground An investigation of an invasive plant species in biodiverse-rich areas, and measures of removal for ecosystem restoration. Universitetet i Oslo. Full text in Research Archive
• Prydz, Kristian; Maciej-Hulme, Marissa & Brændshøi, Vebjørn (2026). Investigating the glycosylation of Syndecan-1 and CRISPR editing of glycosaminoglycan sites. Universitetet i Oslo. Full text in Research Archive Show summary

  Syndecan-1 (SDC1) is an important proteoglycan (PG), which is involved in aspects such as cell morphology, cell-to-cell adhesion, and signal transduction. Long, negatively charged, and heavily sulfated polysaccharides known as glycosaminoglycans (GAGs) are attached to SDC1 and mediate many of its functions. SDC1 has five GAG attachment sites, i.e., serine residues followed by a glycine, to which heparan sulfate (HS) or chondroitin sulfate (CS) chains are attached. As with most PGs, both the overall GAG content and the structure of individual GAG chains on SDC1 vary substantially between tissues, cell types, and even among individual cells. SDC1 has been implicated in various forms of cancer, with changes to protein expression and localization being commonly observed. Despite its involvement and importance in breast cancer, the glycosylation of SDC1 is not fully characterized. To address this, we investigated the glycosylation of SDC1 in the embryonic kidney cell line HEK293T and the triple-negative breast cancer cell line MDA-MB-231 by metabolic radiolabeling with 35S-sulfate followed by enzymatic digestion of GAGs. Generally, site-specific GAG data is limited due to difficulty associated with assigning structural data to specific sites. Thus, we also wanted to genetically modify cells using the CRISPR/Cas9 system to express specific engineered forms of SDC1 in which only one, or a defined subset, of GAG chains were attached. The approach used homology-directed repair with donor DNA to mutate the serine residues of GAG attachment sites, thereby preventing GAG chain attachment. Unfortunately, we were unable to validate successful mutation of GAG attachment sites. However, we did successfully insert a FLAG-tag into the SDC1 gene, indicating that the overall approach is functional but requires further optimization to achieve the edits targeting the GAG attachment sites. Analysis of metabolically radiolabeled SDC1 showed that both HS and CS are present on cell-associated SDC1 from HEK293T and MDA-MB-231, with HS contributing more to its molecular weight than CS. In contrast, CS contributed substantially to the molecular weight of soluble SDC1 released from HEK293T cells. The glycosylation of soluble SDC1 released from HEK293T cells differed considerably from the cell-associated form, including reduced heterogeneity. For MDA-MB-231 cells, the glycosylation of soluble SDC1 appeared to be more like its cell-associated counterpart. Mapping all reported sites of glycosylation on SDC1 revealed a large region of extensive O-glycosylation, an aspect of SDC1 that has received little attention and limited discussion previously.

• Eskeland, Ragnhild; Sekulic, Nikolina; Progida, Cinzia Anita Maria & Svoren, Peter Horvati (2026). Biochemical and Structural Characterization of a Bacteriophage Cox Protein. Universitetet i Oslo. Full text in Research Archive
• Ravinet., José Cerca, Camilo Salazar, Victor Noguerales, Maëva Gabrielli, Mark & Muñoz, Mayelby Geraldine Rueda (2026). An admixed insular lineage of Heliconius cydno from Gorgona Island, Colombia. Universitetet i Oslo. Full text in Research Archive Show summary

  Gene flow, demographic changes, and geographic isolation interact in complex ways during population divergence. These processes can be difficult to disentangle, especially in insular systems, where founder effects and small population sizes may increase genetic differentiation while also blurring historical signals of connectivity through drift. In this study, we used a population genomic approach to investigate the evolutionary history of an insular population of Heliconius cydno from Gorgona Island, Colombia. We analysed whole-genome resequencing data from 46 individuals, including samples from the island population and from three nearby continental populations that share similar wing patterns: H. c. alithea, H. c. weymeri, and H. c. zelinde. We infer that the Gorgona population originated through admixture, after which geographic isolation played a central role in its evolutionary history. Our findings provide multiple lines of evidence supporting this scenario. First, the Gorgona population is genetically distinct, with limited ongoing gene flow with the continental populations. Second, demographic inference indicates a marked reduction in effective population size (Ne), consistent with a single founding episode under conditions of insular isolation. Third, patterns of historical gene flow among the four populations support a hybridization model in which H. c. alithea (59%) and H. c. weymeri (41%) contributed to the origin of the Gorgona population. Finally, we identified genomic regions associated with phenotypic traits in Heliconius, particularly wing-pattern loci (WntA and ivory), where parental contributions align with two specific phenotypic features: the complete forewing band and the intermediate ventral hindwing bar. Keywords: Admixture, demography, gene flow, Gorgona Island, wing pattern, Heliconius cydno.

• Pandey, Hovedveileder: Deo Prakash; Fleischer, Medveileder: Thomas; Paulsen, Intern veileder: Jonas & Jamesrajkumar, Roshman (2026). Integrative multi-omics analyses of transcriptional perturbations in pancreatic cancer cells. Universitetet i Oslo. Full text in Research Archive Show summary

  Pancreatic ductal adenocarcinoma (PDAC) is among the most aggressive cancers with a low survival rate and few treatment options. Cancers are dependent on a sustained transcriptional output to maintain both stress response programs, DNA damage response programs, and lineage-specific regulatory networks. This makes the transcriptional machinery an attractive therapeutic target. Transcriptional cyclin-dependent kinases (tCDKs) are key regulators of transcription, phosphorylating specific Serine residues on the C-terminal domain (CTD) of RNA Polymerase || (RNAP||) to drive the progression through the transcription cycle. CDK12 and CDK13 (CDK12/13), two homologous kinases associated with cyclin K, phosphorylate Serine 2 on the RNAP|| CTD to promote the productive elongation phase of transcription. While inhibition of several transcriptional phases has been extensively studied, recent work has increasingly focused on therapeutic targeting of transcriptional elongation. CDK12/13 inhibition has shown sensitivity across multiple cancer types, including PDAC, where treatment reduces cell proliferation. Therefore, further investigation of how CDK12/13 inhibition affects chromatin accessibility and gene expression is needed. In this thesis, we investigated the genome-wide transcriptional and chromatin response to CDK12/13 inhibition in a PDAC cell line model, using SLAM-seq to quantify nascent RNA dynamics and ATAC-seq to map chromatin accessibility across three treatment time points (2, 4, and 6 hours). Short-term CDK12/13 inhibition led to a rapid and global downregulation of nascent transcription, where candidate gene sets were among the downregulated genes. PDAC-associated transcription factor programs showed strong evidence of selective sensitivity. Integrative analysis revealed that PDAC-specific transcription factors (TFs) were significantly downregulated following inhibition, with their binding motifs enriched in accessible chromatin regions and their target genes showing coordinated repression at the level of nascent transcription. Collectively, these findings suggest that CDK12/13 activity supports maintenance of PDAC-associated transcriptional programs and may represent a therapeutic vulnerability in pancreatic cancer.

• Dalhus, Bjørn; Montaldo, Nicola Pietro; Hersleth, Hans-Petter & Jarlsberg, Kari-Marie Wedel (2026). Identification and characterization of Endonuclease III-like protein 1 inhibitors. Universitetet i Oslo. Full text in Research Archive Show summary

  Defects in DNA repair are closely associated with the development of cancer, neurodegenerative diseases, and other disorders. The human enzyme NTHL1 (endonuclease III-like protein 1) is a DNA glycosylase that plays a central role in the base excision repair (BER) pathway by recognizing and removing small, non-distorting lesions, such as oxidatively damaged DNA bases. Incomplete or defective BER can lead to the accumulation of abasic sites (AP sites) and single-strand breaks, which are often more genotoxic than the original base lesion. Data suggest that removal or inhibition of NTHL1 could have a positive effect on mitochondria in neurodegenerative models such as Parkinson´s disease. The aim of this thesis is to identify and characterize small-molecule inhibitors of human NTHL1 using methods such as recombinant protein expression, biochemical and enzymatic assays, biophysical binding assays, and X-ray crystallography. Recombinant protein expression is used to produce purified human NTHL1, which is then used for biochemical and enzymatic assays to assess catalytic activity and substrate affinity in the presence of candidate compounds. X-ray crystallography is used to obtain structural insight into NTHL1-inhibitor interaction and binding. In this project, a panel of candidate molecules is evaluated for their ability to bind to and inhibit NTHL1. A set of 20 compounds was evaluated for NTHL1 inhibition. The set consists of 15 structurally related analogues designed from a known NTHL1 inhibitor, the known inhibitor itself, and 4 additional small molecules with diverse scaffolds. They all belong to the same scaffold with small structural variations in 2 substituted positions. We have identified 5 high µM inhibitors of NTHL1 in an enzymatic DNA repair assay. However, biophysical binding studies using nanoDSF, fluorescence proximity measurements, and X-ray crystallography did not yield conclusive data to determine enzyme-drug affinity or binding site(s). Still, the thesis shows that compounds of this scaffold could form a basis for further improvement of NTHL1 inhibitors. Enhanced understanding of such inhibitors may ultimately contribute to the development of new tools to study DNA repair in neurodegenerative disease, including Parkinson´s disease, and to clarify how altered BER activity and AP-site formation impact neuronal survival.

• Inngjerdingens,, Marit; Falnes, Pål & Milojic, Milena (2026). Investigating the biogenesis of NK-cell derived cytotoxic extracellular vesicles. Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract and files will be published: 2028-05-15

• Vestad, Beate; Hov, Johannes Espolin Roksund; Saatcioglu, Fahri & Lund, Sandra Arildsdatter (2026). Characterisation of extracellular vesicles in patients with primary sclerosing cholangitis and cholangiocarcinoma. Evaluating effects of pre-analytical variables on circulating EV proteomic profiles in PSC-associated CCA: Implications for EV-based liquid biopsy biomarker discovery. Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract will be published: 2028-05-22

• Maciej-Hulme, Marissa; Prydz, Kristian & Le, Victoria (2026). CRISPR/Cas9-mediated editing of glypican-5: Generation and validation of FLAG-tagged and glycosaminoglycan chain-deficient cell lines. Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract will be published: 2027-05-15

• Øvrevik, Anani Afano, Øyvind P. Haugen, Johan & Asadian, forough (2026). In vitro cytotoxic and pro-inflammatory effects of nanoplastics contaminated with SARS CoV-2 spike protein 1. Universitetet i Oslo. Full text in Research Archive Show summary

  The global increase in plastic production has led to ubiquitous spread of micro- and nanoplastics (MNPs). Nanoplastics can deposit deep in the alveolar regions of the lung upon inhalation due to their small size. This raises public health and occupational concerns. Beyond their physical toxicity, nanoplastics can also act as vectors for pathogens. Following the COVID-19 pandemic, the disposal of plastic protective equipment highlights the need to investigate how nanoplastics can interact with airborne pathogens such as SARS-CoV-2 virus, as they may remain viable on plastic surfaces over longer periods. This thesis investigated the acute pulmonary effects of nanoplastics contaminated with non-infectious SARS-CoV-2 spike 1 protein in a physiologically relevant in vitro air-liquid interface (ALI) lung model, using co-cultured A549 (alveolar type II cells) and THP-1 macrophage-like cells. Cytotoxic and pro-inflammatory responses were assessed after exposing the cells to non-biodegradable nanoplastics (polyethylene terephthalate (PET)), biodegradable nanoplastics (polylactic acid (PLA)), and reference particles SiO2, all as pristine or contaminated with spike 1 protein. Endpoint assays included cytotoxicity through release of lactate dehydrogenase (LDH), and measurement of pro-inflammatory cytokines (IL-6, IL-8, TNFα) at both mRNA transcript and secreted protein levels. Toll-like receptor (TLR) activation was included to screen for microbial component contamination of the test materials. Overall, PET, PLA and SiO2, all in pristine or contaminated state, did not induce significant cytotoxicity in the A549/dTHP-1 ALI model. All particle types triggered pro-inflammatory responses, with SiO2 producing the strongest cytokine release. TLR activation assay showed no activation of TLR2 and TLR4 by the test materials, indicating the absence of microbial components that act as agonists for these receptors. Our results indicate that both the bio- and non-biodegradable nanoplastics can activate early pro-inflammatory responses in epithelial lung and macrophage-like cells without causing acute cell death. In addition, the SiO2 nanoparticles that were used as reference particles tend to induce higher IL-6 and IL-8 levels compared to the nanoplastic particles. The ALI co-culture model implemented in this study provides a physiological relevant platform for assessing acute particle-induced immune effects. However, further research is needed to better understand how nanoplastics interact with viral components. Clarifying their adsorption and cellular uptake mechanisms is essential to assess their role in modulating immune responses and increasing respiratory health risks.

• Bjorå, Prof. Charlotte S.; Zimudzi,, Prof. Clemence; Nelson, Dr. Jessica; Chapano, Dr. Christopher; Hauser, Duncan & Mukahanana, Saymore C. [Show all 11 contributors for this article] (2026). Phylogenetic analyses of the Gloriosa superba L. complex (Colchicaceae) in Africa. Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract and files will be published: 2028-05-22

• Flister, Renate Sæther; Fahlquist-Hagert, Cecilia & Prydz, Kristian (2026). Comparison of finding an optimal model for human xenografts. A comparative study of NSG-SGM3 and NBSGW mouse strains and the effect of Busulfan conditioning on human hematopoietic engraftment. Universitetet i Oslo. Full text in Research Archive Show summary

  Hematopoietic stem cell transplantation (HSCT) is reserved for patients with malignant and non-malignant hematological disorders, in whom other therapeutic options are ineffective. To improve the translational value of HSCT research, robust pre-clinical models are needed to capture human hematopoietic reconstitution niche dependent engraftment. Humanized mouse models provide a useful system for studying the interaction between donor hematopoietic stem (HSC) and progenitor cells and the bone marrow niche. This thesis compares the engraftment efficiency and multilineage reconstitution supported by the NSG-SGM3 and NBSGW mice. Highly purified cord blood-derived CD34+ cells were transplanted into both strains, with groups receiving either busulfan preconditioning (2x 20mg/kg) or no conditioning. Human hematopoietic reconstitution was analyzed in bone marrow, spleen and peripheral blood using conventional and spectral flow cytometry. In addition, donor-host sex matching and sample fixation were evaluated as biological and technical variables affecting data interpretation. Both strains supported human engraftment, but with distinct lineage biases. NSG-SGM3 favored primitive and myeloid-associated output, where NBSGW supported a more lymphoid output, with higher frequence of lymphoid-primed multipotent (LMPP) and pre-B-cell. Busulfan preconditioning provided only limited additional benefits and, in some cases, did not improve human chimerism. Donor-host sex matching did not produce a statistically significant effect, through a trend toward higher cell frequencies in sex-matched was observed. Sample fixation, however clearly reduced marker detection and introduced epitope masking, showing that fresh cells analysis is preferable for reliable high-parameter flow. Overall, the findings indicate that neither NSG-SGM3 nor NBSGW is universally superior. Rather, each model is suited to different biological questions and engraftment success, depending on host background, donor quality, conditioning strategy and analytical workflow. This has a direct relevance for translational HSCT research, where model choice can shape experimental conclusions. The most useful humanized mouse model is therefore not that one performs best in all settings, but the one whose bias best matches the question being asked.

• Fonneløp, Ane Elida; Hofsvang, Aurora & Kjøsnes, Peder Gran (2026). Microbial fingerprinting of soils using bacterial community profiles. Random forest classification for forensic provenance attribution using V4 16S rRNA sequencing. Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract and files will be published: 2027-05-26

• Sollid, Ludvig; Johannesen, Marie Kongshaug; Johansen, Finn-Eirik & Ceballos, Erika Athena Valderrama (2026). Bispecific Autoantigen T cell Engagers in Celiac Disease. Universitetet i Oslo. Full text in Research Archive Show summary

  Celiac disease is an autoimmune disorder driven by an immune response against dietary gluten proteins. The disorder is characterized by antibodies against the autoantigen transglutaminase 2 (TG2), and B cells specific for TG2 are likely central in the pathogenesis. In other autoimmune diseases, therapeutic strategies targeting B cells have shown great promise. Such therapies, either conducted by use of antibodies to B cells (like anti-CD20), bispecific T cell engagers (BiTEs) or chimeric antigen receptor (CAR) T cells against CD19, cause broad B cell depletion. Conceivably, a depletion of the autoreactive B cells rather than all B cells should suffice for therapy. In this project, an approach aiming to selectively deplete autoreactive TG2-specific B cells and plasma cells is explored. The approach utilizes a novel bispecific autoantigen T cell engager (BiAATE) reagent. The BiAATE molecule is designed to consist of TG2 as a bait for TG2-specific B cells, and a single-chain variable fragment (scFv) of an antibody specific for CD3 to engage T cells. This BiAATE reagent should enable formation of an immunological synapse between TG2-specific B cells or plasma cells and cytotoxic T cells, thereby facilitating selective B cell elimination. A cell biology challenge is that TG2 is normally produced in the cytosol on free ribosomes while antibodies are produced in the secretory pathway. To circumvent this problem, the two parts of the BiAATE reagent are produced separately and subsequently covalently coupled using a sortase A enzyme. Moreover, TG2 is mutated to prevent its binding to fibronectin, while still keeping relevant antigenic B cell epitopes intact. To allow for testing in a preclinical mouse model and with human cells, BiAATEs with mouse TG2 and scFv specific for mouse CD3 as well as BiAATEs with human TG2 and scFv specific for human CD3 are produced. In the project recombinant proteins have been expressed, purified and quality tested. Binding of scFv components have been assessed in flow cytometry using human and mouse cells. Coupling of BiAATEs components with two different forms of sortase A reagents has been performed. While the TG2 variants were found to still bind fibronectin, other parts of the approach using BiAATEs have been successfully validated. Testing whether the BiAATEs allow for killing of TG2-specific B cells remains to be done.

• Iversen, Nina; Szymanska, Monika; Prydz, Kristian & Foslie, Marikken Aurora Myhre (2026). Exploring the Function of Factor V in Tumor Infiltrating Lymphocytes. Establishment of a CRISPR/Cas9-Mediated F5 Knockout Model in Primary Human T Cells with Downstream Functional Characterization. Universitetet i Oslo. Full text in Research Archive
• Ciosk, Rafal; Neeb, Synne Lindahl & Heyerdahl, Kristina (2026). Post-transcriptional gene regulation during the oocyte-to embryo transition. Universitetet i Oslo. Full text in Research Archive Show summary

  LIN-41 is an RNA binding protein (RBP) and a member of the TRIM-NHL family of RBPs. In the C. elegans germline, LIN-41 functions as a translational regulator and is associated with the repression of oocyte formation. LIN-41 mediated translational repression occurs through binding to LIN-41 response elements (LREs) of target mRNAs (Kumari et al., 2023). In this thesis, we investigated a potential interaction and regulatory relationship between IFET-1 and LIN-41, as the preliminary data suggested that LIN-41 may mediate translational repression through IFET-1. IFET-1 is a conserved eIF4E-binding protein that functions as a translational regulator in C. elegans germline. Our hypothesis is that LIN-41 could interact with IFET-1, which may indicate additional mechanisms of LIN-41 mediated regulation beyond LRE and 3’UTR dependent repression. Reporter strains were used to assess phenotypes following ifet-1 RNAi knockdown. Initial experiments showed weak ifet-1 RNAi. To strengthen RNAi knockdown, new clones of ifet-1 were constructed and tested on IFET-1 endogenously tagged strain. qPCR analysis was conducted to evaluate the efficiency of the RNAi clones and demonstrated significant depletion of relative ifet-1 mRNA across all clones. Proximity ligation assay (PLA) was conducted to assess potential interaction between IFET-1 and LIN-41. However, no significant interaction was detected, potentially due to multiple technical and biological limitations. This thesis contributes to the understanding of IFET-1 and LIN-41 associated translational regulation.

• Foote, Andrew; Jourdain, Eve & Yannuzzi, Lucia (2026). Genetic Investigations of Population Strucutre among North Atlantic Killer Whales (Orcinus orca). Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract and files will be published: 2028-05-15

• Syljuåsen, Randi G.; Hauge, Sissel & Skåttun, Irmelin Vilde (2026). Evaluation of DNA damage response inhibitors in combination with proton irradiation in glioblastoma cells. Universitetet i Oslo. Full text in Research Archive
• Stedje, Brita; Möller, Erik; Kirika, Paul; Frisch, Andreas; Timdal, Einar & Timdal, Felix Mokoro, Brita Stedje, Erik Möller, Paul Kirika, Andreas Frisch, Einar (2026). The Phyllopsora species of Kenya and Madagascar. Universitetet i Oslo. Full text in Research Archive
• Undheim, Eivind Andreas Baste; Vøllestad, Leif Asbjørn; Ramiro, Iris Bea & Vlassopoulou, Evangelia (2026). Why is the blood of eels toxic? Characterization and evolutionary analysis of the serum toxin in the European eel Anguilla anguilla. Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract and files will be published: 2027-05-15

• Bergersen, Linda Hildegard; Fyhn, Marianne & Svenberg, Guri Marie (2026). Investigating the Neuroprotective Potential of Lactate in an NSC-34 Cell Model of Amyotrophic Lateral Sclerosis-Related Oxidative Stress. Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract and files will be published: 2029-06-01

• Grødeland, Gunnveig; Tjärnhage, Elias; Progida, Cinzia Anita Maria & Porstendorfer, Jesse (2026). A Mouse Model to Assess Immune Imprinting Following Repeated Influenza Virus Infections. Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract and files will be published: 2029-06-01

• Timdal, Einar; Halvorsen, Rune; Möller, Erik Johan & Bruu-Kammler, Teodor (2026). A taxonomic survey of Peltigera didactyla and her sorediate relatives. Towards a taxonomic understanding of the cryptic species diversity in the Peltigera didactyla group. Universitetet i Oslo. Full text in Research Archive
• Inngjerdingen, Marit; Sudworth, Amanda; Griffiths, Gareth Wyn & Soleng, Marius Figenschou (2026). Investigation of the Mode of Delivery of Natural Killer Cell-Derived Extracellular Vesicles to Cancer Cells. Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract and files will be published: 2027-05-15

• Paulsen, Jonas & Ørning, Nadia Elise Helene (2026). Chromosomal Translocations and Their Impact on 3D Genome Organization and Gene Regulation in Breast Cancer Progression. Universitetet i Oslo. Full text in Research Archive Show summary

  Chromosomal translocations are a hallmark of many cancers, but how they affect the three-dimensional (3D) organization of the genome and gene expression is not fully understood. This thesis investigated if translocations in MCF10A breast epithelial cells change how the genome is organized in the nucleus, and if these changes affect gene expression. Three MCF10A cell lines were compared, each representing a different stage of breast cancer progression: wild-type (WT), premalignant MCF10AT1 (T1), and malignant MCF10Ca1a (C1). 3D genome models were built from Hi-C data using Chrom3D. The spatial distances between translocated genes and their neighbors were measured, and the radial position of translocated segments in the nucleus was calculated. Compartment and subcompartment organization was analyzed to see if translocated regions kept their chromatin identity or changed it. Finally, RNA-seq data were used to look at gene expression changes in translocated regions. The 3D distance analysis confirmed the structural consequences of the translocations. Genes from different chromosomes are brought closer together in space, while moving away from their original neighbors. These spatial changes appear to be largely present already in the premalignant T1. Chromatin reorganization, on the other hand, developed progressively from T1 to C1. This suggests that translocations create the structural conditions for chromatin remodeling, but that the remodeling itself unfolds over time during malignant progression. Most translocated regions kept their broad A or B compartment identity. At the finer subcompartment level, however, reorganization was much greater and increased with cancer progression. The most reorganized translocation, t(3;17), involves two chromosomes with very different chromatin profiles. Its two derivative chromosomes reorganized in opposite directions: one toward active A-type states and the other toward inactive B3. This suggests that the bigger the mismatch between the exchanged segments, the more reorganization occurs. The radial positioning analysis showed that small translocated fragments can be moved within the nucleus by their new chromosomal environment, while larger fragments change their chromatin identity but stay in place. Gene expression changes followed the same progressive pattern. In T1, translocated genes showed no significant enrichment for differential expression. In C1, significant enrichment was found, together with a bias toward upregulation. GO analysis identified affected biological processes such as developmental regulation, mammary gland development, and cell cycle control. The link between chromatin reorganization and gene expression was subtle, with 3D genome organization appearing to fine-tune expression levels rather than switching genes on or off. The main finding of this thesis is that the structural and transcriptional consequences of chromosomal translocations develop gradually during cancer progression. The full impact cannot be understood from a single time point or a single level of genome organization.

• Boessenkool, Sanne; Frank, Lea & Sveen, Carina (2026). Holocene distribution of marine biodiversity preserved in caves along the coast of Norway: The fish tale of Solsemhula. Universitetet i Oslo. Full text in Research Archive
• Mørch, Mikkel Martinussen; Hyvärinen, Olli Petteri; Eiler, Alexander; Werner, Even; Gagnon, Karine & Thormar, Jonas (2026). Biodiversity patterns and blue carbon characteristics of Zostera marina meadows in the Oslofjord. Universitet i Oslo. Full text in Research Archive Show summary

  Seagrass meadows are coastal foundation habitats that support biodiversity and store organic carbon in sediments, a process often referred to as blue carbon storage. However, both biodiversity and sediment carbon storage can vary strongly among meadows, and it remains unclear how local meadow structure, hydrodynamic exposure, organic-matter sources, and associated fauna interact in temperate eelgrass systems. This thesis investigated biodiversity and blue carbon characteristics of Zostera marina meadows in the Oslofjord, Norway. The study combined two complementary approaches: citizen-science-based environmental DNA (eDNA) water sampling across eelgrass meadows and seasons, and researcher-led field sampling at three meadows along an inner-outer Oslofjord gradient. The field-sampled meadows represented contrasting coastal settings: an inner-fjord meadow at Fornebu, a sheltered meadow near Sætre/Sandspollen, and a more wave- exposed outer-fjord meadow at Holmestrand. The water eDNA dataset provided broad spatial and seasonal coverage, but ecological interpretation was limited by uneven sampling and read-depth loss after filtering. After taxonomic partitioning of the cytochrome c oxidase I (COI) metabarcoding dataset, only 20.5% of reads were retained as faunal reads, while 79.5% were classified as non-faunal reads. The retained faunal water eDNA dataset did not show clear winter-spring or Oslofjord-section structure. Instead, it contained a mixed coastal signal, including pelagic planktonic taxa and benthic or soft-sediment-associated taxa. In contrast, the non-faunal fraction showed clearer winter-spring structuring, largely associated with microalgal and protist groups. This indicates that broad COI water eDNA can capture useful biodiversity signals, but also that faunal and non-faunal datasets should be separated before ecological interpretation. The strongest ecological patterns were found in the field-measured meadows. The sheltered Sætre/Sandspollen meadow had continuous eelgrass cover, low sediment bulk density, high and consistent organic carbon stocks, and the highest apparent seagrass-like carbon contribution. The more wave- exposed Holmestrand meadow was patchier and had higher bulk density, lower organic carbon stocks, and the lowest apparent seagrass-like carbon contribution. The inner-fjord Fornebu meadow had intermediate sediment carbon stock, bulk density, and apparent seagrass-like carbon contribution, but showed greater within-meadow variability. Stable isotope composition supported these meadow-level differences and indicated variation in both carbon-source characteristics and assimilated nitrogen among meadows. Benthic eDNA showed clear separation between seagrass-blade epifaunal communities and sediment-core infaunal communities. Infaunal communities were most strongly associated with sedimentary gradients and were dominated by sediment-associated annelids, including lugworms and other ii taxa linked to deposit feeding, burrowing, sediment reworking, and bioirrigation. In contrast, the epifaunal signal was dominated more strongly by sessile or surface-associated taxa, including barnacles, bryozoans, and hydrozoans, rather than by mobile mesograzers. Overall, this thesis shows that eelgrass meadows in the Oslofjord can differ substantially in meadow structure, sediment carbon characteristics, stable isotope composition, and associated benthic fauna. The results support a descriptive interpretation in which blue-carbon characteristics and benthic biodiversity vary together at local meadow scale, particularly through the association between sediment conditions and infaunal community structure. Broader inference about Oslofjord-wide seasonal biodiversity patterns will require more balanced repeated sampling but the study demonstrates the value of combining citizen-science water eDNA with targeted field measurements when assessing biodiversity and blue carbon in eelgrass meadows.

• Wood, Ethan (2026). Phycosphere microbiome dynamics in filamentous algae: community composition, stability, and patterns across cultivation scales in phycoremediation systems. Universitetet i Oslo. Full text in Research Archive Show summary

  Algae can be used to recover nutrients from municipal wastewater as biomass. This approach supports a more circular use of resources, but it also exposes algae to highly diverse microbial communities that may influence productivity and cultivation stability. This thesis investigated the bacterial communities associated with filamentous green algae used in wastewater treatment. Across laboratory and pilot-scale experiments, many bacteria remained associated with the algae even after prolonged exposure to wastewater communities. Different algal cultures often shared similar groups of bacteria; however, they differed in the specific bacterial strains they contained. These differences were influenced by both the history of the algal cultures and the algae themselves. Together, these findings show that the bacterial communities present in stock algal cultures can have lasting effects on the bacterial communities that develop during wastewater treatment. This supports further research into whether algal microbiomes are steerable and whether this could help improve the management of algal cultivation systems used for wastewater treatment and biomass production.

• Thorstad, Eva Bonsak; Forseth, Torbjørn; Bolstad, Geir Hysing; Einum, Sigurd; Falkegård, Morten & Fiske, Peder [Show all 16 contributors for this article] (2026). Status for norske laksebestander i 2026. Vitenskapelig råd for lakseforvaltning. ISSN 9788293038450. Full text in Research Archive Show summary

  Antallet laks som kom fra havet til Norge i 2025 var høyere enn bunnåret 2024, men norsk villaks er fortsatt på et historisk lavt nivå. Laksebestandene har vært på et lavt nivå i mange år, og de fem siste årene har det vært en ytterligere nedgang. Det er spesielt laksebestandene i Midt-Norge og Vest-Norge som har en negativ utvikling. Årsaken til de reduserte laksebestandene er de menneskeskapte truslene og lav overlevelse i sjøen. De største truslene er lakseoppdrett og klimaendringer. Det var ingen bedring for noen av de menneskeskapte truslene mot laks siden forrige vurdering. Pukkellaks er det eneste menneskeskapte påvirkningen med økt risiko for ytterligere skade siden forrige vurdering - og samtidig er kunnskapen om effektene av pukkellaks svært mangelfull. Laksen i Tanavassdraget er sterkt truet. Hovedårsaken er tidligere overbeskatning. Selv om fisket er stanset i både vassdraget og i sjøen, er det svært krevende å bygge opp bestandene i vassdraget fra dagens kritisk lave nivå.

• Forseth, Torbjørn; Thorstad, Eva Bonsak; Bolstad, Geir Hysing; Einum, Sigurd; Falkegård, Morten & Fiske, Peder [Show all 16 contributors for this article] (2026). Kunnskap og råd om fiskeutsettinger. Vitenskapelig råd for lakseforvaltning. ISSN 9788293038436. Full text in Research Archive Show summary

  I denne rapporten er formålene å 1) oppsummere bruken av fiskeutsettinger i Norge, 2) oppsummere nasjonal og internasjonal kunnskap om genetiske og økologiske effekter og mulig risiko knyttet til fiskehelse, og 3) gi råd om fiskeutsettinger. Antall vassdrag med fiskeutsettinger har blitt betydelig redusert, fra tidligere over 200 vassdrag til 37 vassdrag i 2025. Fiskeutsettinger gir bare ønsket kortsiktig positiv effekt under spesielle betingelser og medfører stor fare for langsiktige skadelige effekter på bestandene. Denne konklusjonen har blitt styrket gjennom nye undersøkelser. Utsettinger kan under strenge betingelser være med å redde laksebestander som holder på å gå tapt, men slike redningsaksjoner vil gjerne mislykkes om ikke årsakene til den negative bestandsutviklingen er fjernet. Utsettingsprogram som har som hensikt å øke det høstbare overskuddet bør opphøre, og nye bør ikke startes. Fiskeutsettinger bør ikke fortsette eller startes for å kompensere for tap som skyldes menneskeskapte påvirkninger, fordi det er godt dokumentert at fiskeutsettinger over tid svekker bestandene. Håndtering av påvirkningene og tiltak for å bedre miljøforholdene for fisken må prioriteres.

• Lu, Xiang (2026). Boreal lakes as mediators for terrestrial organic carbon processing and greenhouse gas emissions: a case study from Langtjern Norway. Universitetet i Oslo. Full text in Research Archive Show summary

  Boreal lakes receive and process substantial inputs of terrestrial derived dissolved organic matter (DOM), yet few studies systematically investigate their carbon dynamics and greenhouse gas (GHG) emission. This thesis integrated long-term empirical datasets, in‑situ high‑frequency monitoring, intensive field campaigns, dark incubations, and stable carbon isotope analyses to study the carbon mass balance and dynamics in lake Langtjern and assess its source-sink function in the catchment carbon budget. We found terrestrial DOM input drives in-lake DOM levels whereas water residence time governs DOM removal rates. The lake is a substantial source of GHGs, and its carbon evasion is dominated by CO2 (>99%) with CH4 < 1%. In‑lake CO2 production is the primary source of emitted CO2, and sediment respiration is the largest contributor. The microbial mineralization rate of lake DOM is driven by temperature, and regulated by solar radiation and C:N of DOM. We anticipate the influence of wetting (negative) may outweigh that of warming (positive) in regulating lake DOM removal rate. The increasing hydrological flushing could shift sediments from carbon sink to carbon source. Extreme rainfall events can substantially increase lake GHG emissions by promoting lake mixing. Under a wetter climate, catchment soil can be a net carbon source.

• Titov, Aleksei & Strømsnes, Lynn Kristin (2026). Identification of T cell cross-reactivity towards allogeneic HLA class I molecules. Universitetet i Oslo. Full text in Research Archive Show summary

  --- Abstract will be published: 2028-05-15

• Wennberg, Aina Charlotte (2026). Developing novel methods for persistence assessments of chemicals of emerging concern: To be or not to be? That is the question. Universitetet i Oslo. Full text in Research Archive Show summary

  How do we know if chemicals will persist in the environment? Although chemicals are essential for our modern lives and society, pollution from chemicals is also a threat to the environment and human health. A key factor for environmental concern from pollution is whether a chemical resists degradation and can thus persist in the environment. This project has identified points for improvement of the current methods used for assessing persistence: A database (PikMe) with information on over a million chemicals was created. The information from both tests and predictions from multiple sources where combined but only 5.1% (58 213 chemicals) had reliable data for persistence assessments. In conclusion, PikMe could be improved by adding more data sources and including different prediction methods. The second paper explored why there is so much variability in the test for biodegradation in seawater. Several factors, related to collecting and handling the seawater, affected the degradation rate of the reference chemical aniline. Finally, a laboratory method was developed for high throughput screening of readily degradable chemicals by measuring the growth of bacteria consuming the chemicals as a surrogate for biodegradability. This method provided more insight into how the bacterial communities responded to chemicals, but it was considered not a reliable method for measuring biodegradation.

• Boccara, Charlotte; Modi, Brijesh; Fyhn, Marianne & Horn, Solveig (2026). Behavioral Paradigms for Investigating Cognitive Development and Early-Life Sleep Disruption in Rodents. Universitetet i Oslo. Full text in Research Archive Show summary

  Early postnatal cognitive development in mammals provides the foundation for learning, decision-making, and adaptive behavior throughout life, and is characterized by rapid maturation of neural circuits, coinciding with a substantial amount of sleep. Although sleep is increasingly recognized as critical to early neural development, its specific role in cognitive maturation remains poorly understood. To address this knowledge gap, long-term consequences of early-life sleep disruption can be examined using appropriate animal models. Rats are a promising candidate because their sleep-regulatory mechanisms and neurodevelopmental trajectories parallel those of humans. Furthermore, some of their key neurodevelopmental processes occur within the first postnatal weeks. However, behavioral investigations of young rats remain challenging due to their limited motor and sensory abilities. This thesis aims to contribute to this research by refining the delayed non-match to position protocol (DNMP) task in the Y-maze to assess spatial working memory in developing rats (between postnatal day 15 and 30). I demonstrate that, following a novel habituation protocol, the animals were able to acquire the task with consistent learning curves. I also rule out potential confounders such as self-odor cues, reward guidance and spontaneous alternation with a comprehensive set of control experiments. To test the effect of sleep deprivation on task acquisition, I implemented an orbital shaker-based sleep restriction protocol during a critical developmental window for hippocampal and prefrontal cortex maturation (postnatal day 15 to 19). Although this intervention did not significantly affect the task success rate, I found that the sleep-restricted rats required a significantly longer time to perform the task, suggesting decreased task engagement or subtle alterations in neurodevelopmental processes. Together, these results provide a behavioral framework for cognitive testing in developing rodents, and establish a foundation for future investigations into how early-life sleep perturbations may affect cognitive functions.

• Nygård, Kamilla Børve (2026). Exploring the function and enzymology of protein methylation in skeletal muscle. Universitetet i Oslo. Full text in Research Archive Show summary

  Protein methylation is a fundamental process in which a small chemical group (CH3) is added to proteins by enzymes called methyltransferases. These modifications play an important role in regulating and optimizing protein function. In skeletal muscle, several proteins are known to be methylated. However, for many of these, the functional relevance of the modification, as well as the responsible enzyme, remains elusive. This thesis therefore explores the biological role of these modifications and identifies the enzymes involved. A protein of particular interest is the motor protein myosin, which for several decades has been known to be methylated at several positions. In this work, we identify the enzyme responsible for methylating a site located near myosin´s ATP-binding region, suggesting a role in optimizing its activity. In addition, we show that METTL21C, an enzyme predominantly expressed in skeletal muscle, modifies the contractile protein fast myosin-binding protein C (fMyBPC). Notably, this modification appears to be restricted to certain muscle types. Taken together, the findings demonstrate that muscle-specific methyltransferases target functionally relevant muscle proteins, highlighting protein methylation as an important mechanism in regulating the contractile machinery, muscle specialization, and potentially disease.

• Garvang, Even Sletteng (2026). The impact of microbial parasites on copepods: quantitative answers to a century-old mystery. Universitetet i Oslo. Full text in Research Archive Show summary

  Pelagic copepods are possibly the most abundant group of animals on the planet, and are central in marine food webs. Copepods host numerous parasites with detrimental effects. However, these parasites have mostly been ignored since their discovery more than 100 years ago. In my thesis I have combined field sampling, experiments and modeling to investigate the occurrence of copepod parasites and their effects on individuals, populations and communities. An initial modeling study showed that the population impact of copepod parasites may be large, and pinpointed important parasite traits for infection dynamics. Combining estimates based on the literature with new experiments we found that the release of parasite spores scales with host size, and that larger copepods experience higher infection pressure. We quantified mortality increase and behavioral change induced by the elusive Yellow-Hyphal Parasite, and found that infection was associated with an altered bacterial microbiome. Using a combination of molecular methods and biomass data, we found widespread parasitism year-round in the Oslofjord. Parasite prevalence reached a seasonal peak of 100%, and was often over 50%. This thesis shows that the parasites of copepods are widespread and prevalent, and may play a larger role in plankton ecology than previously believed.

• Nowicki, Robynne (2026). Seasonal energetics in Barents Sea macrozooplankton and fish. Universitetet i Oslo. Full text in Research Archive Show summary

  All living things require energy. Thus, energy connects all living things. As such, the connective nature of energy can be harnessed as a powerful tool in ecology, as a connection from organism to ecosystem. Using this tool, I explored drivers and patterns of energy dynamics of zooplankton and fish in the Barents Sea, an Arctic region strongly affected by climate change. Seasonality in the Arctic is extreme, and so there was a particular focus on the seasonal changes in the energy contained in zooplankton and fish, and how this was further affected by factors like body size, temperature and what prey is available to eat. I found that energy is anything but constant, and instead the energy content changed over the year, as well as throughout life. These organisms had “critical windows”, when their energy stores were very low and they may be more vulnerable to stress. Energy patterns were also species specific, which means that climate-induced shifts in species dominance can benefit some predators whilst being detrimental for others. Overall, this work reveals hidden complexity of energy landscapes and improves our ability to predict how climate-driven change will affect marine ecosystems in a future Arctic.

• Rogge, Frederik Sebastian; Fyhn, Marianne; Malthe-Sørenssen, Anders; Lepperød, Mikkel Elle & Lensjø, Kristian (2026). Normative and Experimental Analyses of Learning-Dependent Representations in the Hippocampal-Parahippocampal System. Universitetet i Oslo. Full text in Research Archive Show summary

  The brain is thought to build a cognitive map of both physical and abstract spaces, helping us navigate the world, organize knowledge, and form new memories. In this thesis, I investigated key brain subregions to uncover the principles underlying the emergence of neural representations. I focused on the general properties of the neural code, how visual inputs are integrated, and how these representations reorganize through learning. To address these questions, I combined large-scale chronic two-photon calcium imaging in mice with normative modeling in artificial neural networks. We show that neurons in the medial entorhinal cortex (MEC) develop task-relevant tuning during learning of a purely visual association task, pointing to a broader role beyond its classical link to spatial coding. In parallel, selective disruption of specific neuron types in the postrhinal cortex (POR) impaired learning of the same task, demonstrating their causal contribution. Furthermore, using artificial neural networks, we uncovered computational principles governing how spatial representations emerge and transform. Finally, we revealed dissociable contributions of POR and MEC to visually guided navigation, highlighting their distinct roles. Together, these results shed new light on the emergence of neural representations in different brain regions and their transformation through learning.

• Noordzij, Hanna Theodora (2026). Dispersal of antibiotic resistance genes and mobile genetic elements in the human infant gut. Universitetet i Oslo. Full text in Research Archive Show summary

  The PhD project produced new knowledge about antibiotic resistance and mobile elements in the infant gut microbiota. It was already known that infants have more antibiotic resistance within their gut compared to mothers or other adults. The thesis provides additional evidence of higher abundance of both antibiotic resistance and mobile elements. The bacterial species Escherichia coli was found as a main contributor of these high abundances. Fortunately, Escherichia coli is generally replaced by more favorable species during the maturation of the infant gut microbiota. However, there is a reasonable concern that antibiotic resistance genes are transferred to pathogens during early life. Disease caused by the now resistant pathogen can be difficult to treat. Plasmids, one of the mobile elements, can carry and transfer antibiotic resistance genes between bacteria. To study plasmids within the complex ecosystem of the human infant gut is methodologically challenging. The thesis significantly improves current (bioinformatic) methods for assignment of plasmids to their bacterial host. This will aid future studies to uncover bacterial hosts of resistance plasmids within a complex ecosystem. Moreover, the method gives an indication of plasmid transfer risk when multiple species or genera are associated with the same plasmid.

• Bronken, Eidesen, Pernille & Embla, Imset, (2026). Colour of sex - Investigating a possible relationship between flower colour and reproduction strategy in Arctic flowering plants. Universitetet i Oslo. Full text in Research Archive Show summary

  Several studies have confirmed an association between blue flowered plants and reproduction by cross-fertilisation. However, few studies have looked at an association between white flowered plants and reproduction strategies. It has been suggested that white flowered plants mainly reproduce through selfing and asexual reproduction, and this association has been confirmed in certain taxa, but has not been shown on a larger scale. This master thesis investigated whether Arctic selfing/asexual plants with flowers initially adapted for insect pollination had a higher probability of being white. Flower colour, reproduction strategies, ploidy level and distribution were mapped and registered for 379 Arctic flower species through an extensive literature search, and traits were tested for correlation using a variety of different analysis methods. The results confirmed what previous studies have only suggested; that selfing/asexual plants are significantly and positively associated with being white. This supports the prediction that blue flowers serve as a reliable signal for pollinator reward (i.e. food like nectar or pollen) – and thus attractive for pollinators but are too costly to produce for plants that do not need pollinators, giving white flowered plants an advantage when pollinators are scarce. When looking at ploidy level, the same association between white flower colour and selfing/asexual reproduction strategy was found in diploids, however polyploids only showed an association between blue flowered plants and being outcrossing, probably due to the species composition in the matrix and the higher levels of homozygosity in diploids. The results also showed that the mean frequency of white selfing/asexual plants was higher in the High-Arctic than in the Low-Arctic and in heavy glaciated floristic regions compared to non- glaciated regions. This indicates that traits such as white flower colour and selfing/asexual reproduction strategies give plants an advantage, with white selfing/asexual plants being better adapted to colder and harsher environments and being more successful when colonizing previously glaciated regions. These results are in accordance with the prevailing hypotheses in the scientific community.

• Brodersen, Andrea M (2026). Patient Stratification in Leukemic Diseases. A computational approach for patient stratification and mechanistic understanding using ex vivo drug screens. Universitetet i Oslo. Full text in Research Archive Show summary

  This thesis shows that testing how leukemia (blood cancer) cells respond to medicines outside the body can help doctors choose better treatments for each patient. This approach, called ex vivo drug sensitivity testing, reveals which medicines work on a person’s cancer cells before treatment begins. It can also uncover new drug combinations that may help fight fungal infections, which can be life-threatening for patients with weakened immune systems. Leukemia is challenging to treat because patients respond very differently to therapy, and many are too weak or ill from infections to tolerate strong chemotherapy. Current methods for choosing treatment mainly rely on genetics, which is useful but often incomplete. We therefore need new tools that give a clearer picture. By combining drug response data with clinical and genetic information, this work shows that drug sensitivity testing can predict treatment outcomes more accurately than traditional markers, especially in acute myeloid leukemia. It also highlights important differences between patients and reveals new clues that may guide treatment in chronic lymphocytic leukemia. The study further identifies promising drug combinations that could help address antifungal resistance. Overall, the findings support a more precise and personalized approach to treating leukemia and protecting vulnerable patients from severe fungal infections.

• Kopcil, Pavel (2026). CRISPR/Cas9-based Strategies for ADA2 Inborn Error of Immunity. Universitetet i Oslo. Full text in Research Archive Show summary

  We show that gene editing can correct a rare immune disorder called DADA2. Using CRISPR, a “molecular scissor,” we fixed a single-letter error in the ADA2 gene with high precision (up to 80%) and tested adding a healthy copy of the gene as a broader solution. Edited blood stem cells stayed healthy, made balanced blood cell types, and worked in mice. DADA2 often starts in childhood and can cause serious illness. Current treatment can be a stem cell transplant from a donor, but donors are scarce and the procedure can fail. Our work points to a patient-tailored therapy that uses a person’s own stem cells, and a near-universal option that could help many patients regardless of their exact mutation. The tools are powerful and flexible, and they could change how we treat rare genetic diseases. But cutting DNA can introduce risks, such as unwanted changes. Therefore, we tested safety in several ways and found encouraging results, yet more work is needed to ensure long-term safety before clinical use.

• Peeters, Bart; Burnett, Hamish Andrew; Mysterud, Atle; Tranulis, Michael A.; Jensen, Magnus Østgård & Jensen, Henrik [Show all 8 contributors for this article] (2026). Villreinbestandenes genetiske sårbarhet for skrantesjuke: Kartlegging og muligheter for genetisk overvåking. Norsk institutt for naturforskning (NINA). ISSN 9788242655479. Full text in Research Archive Show summary

  Peeters, B., Burnett, H.A., Mysterud, A., Tranulis, M.A., Jensen, M.Ø., Jensen, H., Martin, M.D. & Hansen, B.B. 2026. Villreinbestandenes genetiske sårbarhet for skrantesjuke: kartlegging og muligheter for genetisk overvåking. NINA Rapport 2716. Norsk institutt for naturforskning. Skrantesjuke (Chronic Wasting Disease, CWD) ble påvist hos villrein i Nordfjella sone 1 i 2016, og seinere også på Hardangervidda. Det er behov for et styrket kunnskapsgrunnlag for risikovurdering og prioritering av forebyggende tiltak mot etablering og videre spredning av CWD. Denne rapporten kartlegger de norske villreinbestandenes genetiske sårbarhet for CWD ved å beskrive forekomsten av varianter i prionproteingenet (PRNP), og ved å utvikle en metodikk for å predikere PRNP genotyper fra genetiske data under arbeidet med kvalitetsnormen. Dette kan bidra til kostnadseffektiv genetisk overvåking av CWD. Vi sekvenserte PRNP genet til 660 individer fra 22 villreinområder. Disse individene var tidligere også genotypet på SNP arrayet som brukes i arbeidet med kvalitetsnormen. PRNP sekvensene var av tilstrekkelig kvalitet for 590 individer, og seks PRNP varianter (A F) ble bestemt fra sekvensdata. Basert på SNP arraydata valgte vi 122 SNP er på kromosom 11 innen et 1 megabase (Mb) vindu fra starten til PRNP genet og imputerte PRNP variantene med BEAGLE. Ti gangers kryssvalidering viste svært høy presisjon: 99,4 100 % samsvar mellom imputert og observert genotype (R² = 0,95 1,00). Feilratene var lave (falsk positiv 0,0 0,4 %; falsk negativ 0,0 5,6 %), og de største avvikene gjaldt den sjeldne varianten F. Datagrunnlaget økte til 1001 individer etter imputasjon av PRNP genotyper fra SNP arraydataene. De vanligste PRNP variantene var A (andel 0,42) og B (0,36), mens D (0,10) og E (0,09) var moderat vanlige, og C (0,01) og F (0,02) var sjeldne. Det er tidligere vist fra CWD positive dyr i Nordfjella og Hardangervidda at variant A og C er mer mottakelige for CWD enn B, D og E, mens mottakelighetsgrad for variant F er ukjent. Fordelingen av varianter viste en tydelig gradient knyttet til bestandenes genetiske innblanding fra tamrein: bestander med genetisk villreinopphav hadde høy frekvens av A, mens bestander med tamreinopphav hadde høyere frekvenser av mindre mottakelige varianter (særlig B, D og E). Variant F forekom utelukket i bestander fra Dovre Rondaneregionen. Vi beregnet en indeks for genetisk sårbarhet for CWD i villreinbestandene basert på tidligere funn fra Nordfjella og Hardangervidda, og fant en sterk negativ sammenheng mellom sårbarhet og genetisk likhet med tamrein (r = 0,89). Bestander med lavere genetisk sårbarhet kan i praksis fungere som en buffersone, for eksempel mellom Nordfjella og Dovre Rondaneregionen, ved å redusere sannsynligheten for trinnvis romlig spredning av smitte. Indeksen er et mål på genetisk predisposisjon for CWD og må tolkes sammen med smittepress, bestandstetthet, kontaktmønstre og miljøsmitte. Pågående smitteforsøk vil også kunne forbedre kunnskap om mottakelighetsgraden til de ulike variantene, og dermed gi grunnlag for å videreutvikle sårbarhetsindeksen og justere klassifiseringen. Vi viser også at fordelingen av PRNP genotyper i Nordfjella var tilnærmet lik mellom sone 1 (prøver tatt før og under bestandssanering) og sone 2. Reetablering av sone 1 med dyr fra sone 2 vil derfor neppe endre den opprinnelige genetiske sårbarheten for CWD, med mindre reetableringen inkluderer systematisk prøvetaking som gjør PRNP screening og eventuelt seleksjon av grunnleggerdyr mulig som risikoreduserende tiltak. Resultatene er relevante for både CWD overvåking og kvalitetsnormarbeidet, siden PRNP genotyper kan imputeres fra SNP arraydata som likevel skal samles inn jevnlig. Dette kan gi et kostnadseffektivt grunnlag for å vurdere endringer i genetisk predisposisjon for CWD som supplement til helseparameteren i delnorm 1. Videre kan resultatene inngå i sårbarhetsanalyser og i tiltaksplaner, hvor det må gjøres lokale avveiinger mellom tiltak som reduserer negative barriereeffekter og hensynet til å begrense trinnvis smittespredning.

• Rolandsen, Christer Moe; Moorter, Bram Van; Heim, Morten; Johnsen, Bjørnar; Mattisson, Jenny & Brealey, Jaelle C. [Show all 13 contributors for this article] (2026). Elgprosjektet i Oppland 2019-2024. Sluttrapport. Norsk institutt for naturforskning (NINA). ISSN 9788242652249. Full text in Research Archive Show summary

  Rolandsen, C. M., Van Moorter, B., Heim, M., Johnsen, B., Mattisson, J., Brealey, J. C., Miller, A., Utaaker, K. S., Davidson, R. K., Grimsgaard, A., Mysterud, A., Wam, H. K., Solberg, E. J. 2026. Elgprosjektet i Oppland 2019–2024 – Sluttrapport. NINA Rapport 2416. Norsk institutt for naturforskning. Prosjektet ‘Elgen i Oppland’ ble igangsatt etter initiativ fra 11 kommuner og flere jaktrettshavere som helt eller delvis inngikk i tidligere Dokkfløy elgregion. Elgregionen omfattet en stor og delvis sesongtrekkende elgbestand i tidligere Oppland fylke, men som følge av uenigheter om årlig avskyting og uttak av trekkelg i vinterbeiteområdene ble regionsamarbeidet oppløst i 2013. Lokalt er det likevel et sterkt ønske om en felles forvaltning av elgstammen, og over lengre tid har det vært diskutert hvordan de ulike aktørene på nytt kan tilnærme seg et regionalt samarbeid. Det ble da tidlig påpekt behov for bedre og mer oppdatert kunnskap om elgens områdebruk i regionen, og etter en lengre prosess ble det besluttet å etablere et nytt elgmerkeprosjekt i området. NINA ble invitert med i prosjektutformingen, og gjennomførte senere prosjektet innenfor rammene gitt av en lokalt forankret styringsgruppe. I rapporten viser vi resultatene fra prosjektet som pågikk fra september 2019 til august 2024. Prosjektets overordnede mål har vært å øke kunnskapsgrunnlaget om elgen og beitegrunnlaget i tidligere Dokkfløy elgregion. Mer spesifikt var det et ønske å undersøke elgens trekkmønster og habitatbruk, samt å få bedre kunnskap om elgens kalveproduksjon og overlevelse. Dette er kunnskap som best kan oppnås ved å merke et representativt utvalg elg med GPS-sendere for deretter å studere disse individenes bevegelser, reproduksjon (antall fødte kalver) og overlevelse. I starten av prosjektperioden merket vi derfor 52 elger med GPS-sendere og fulgte disse inntil de døde, mistet halsbåndet eller vi aktiverte ‘drop-off’-mekanismen sommeren 2024. Alle elgene ble merket innenfor det mest markante nordlige (Murudalen, Sjodalen, Randsverk, Tesse, n = 36) eller sørlige (Gausdal Vestfjell, n = 16) vinterområde i regionen. Dette er områder med høye konsentrasjoner av elg vinterstid, hovedsakelig som følge av trekkende individer, og som derfor preges av høyt beitetrykk og beiteskader for skogbruket. I tillegg til merkestudiet undersøkte vi beitegrunnlaget og beitetrykket i regionen, og brukte jaktrelaterte data (sett og felt elg-data, slaktevekter) og trekkelgtellinger til å beskrive utviklingen i bestandstetthet, sammensetning og kalveproduksjon. Dette er viktig bakgrunnsinformasjon om bestand og næringsgrunnlag, og kan bidra til å forstå den romlige og tidsmessige fordelingen av elgen i området. Som et ledd i en langt større studie fra flere bestander analyserte vi også parasittforekomsten hos elgen i regionen og sammenlignet denne med tilstanden i andre bestander i Norge. Resultatene fra merkestudien viser at elgene i regionen beveger seg over store avstander og at områdebruken i svært liten grad holdt seg innenfor en kommune. Hele 86 % av de 51 elgene var sesongtrekkende, 14 % var stasjonære i minst ett år, mens kun ett individ ble klassifisert som stasjonær i begge år med data. De fleste individene brukte arealer i 4–5 kommuner (2–8) i løpet av et år. Gjennomsnittlig trekkdistanse var 47 km for elgkyr og 50 km for elgokser, men mange dyr hadde trekk på over 70–80 km mellom vinter- og sommerområder. Det lengste dokumenterte trekket var på 135 km i luftlinje – fra nordsiden av Vågåvatnet til Gjøvik. De sesongtrekkende individene beveget seg hovedsakelig mot sørøst på våren og tilbake mot nordvest på høsten. Mange av disse beveger seg da gjennom Espedalen, på grensen mellom Sør-Fron og Gausdal. Årlig registreres det her spor fra 600–800 elger på veg sørover fra Murudalen på våren (systematisk vårtelling utført langs fast transekt av lokalt mannskap), hvorav om lag to tredeler fortsetter gjennom Espedalen på sørvestsiden av vannet. Dalføret er relativt smalt, og trekkorridoren er sjeldent mer enn én kilometer bred. Også elgene i vinterbeiteområdet i Gausdal Vestfjell beveger seg mot sørøst på våren og tilbake mot nordvest på høsten, blant annet i dalføret ved Dokkfløyvatnet. Sesongtrekkene gjenspeiler elgens behov for å oppsøke sesongleveområder med gode forutsetninger for vekst og overlevelse. Vinterområdene i regionen kjennetegnes av mindre snø og mer lett tilgjengelig kvistbeite (særlig bjørk og furu), mens sommerområdene for det meste ligger lavere, har bedre feltsjikt og rikere tilgang på vier og dels rogn og selje. I tillegg er elgtettheten lavere i mange av sommerområdene, noe som reduserer konkurransen om ressursene. En slik kombinasjon av snøforhold, planteproduksjon og tetthetsavhengighet er trolig hovedforklaringen på hvorfor elgene gjennomfører så omfattende trekk. GPS-dataene viser samtidig at elgens bruk av vinterområder ikke er statisk mellom år. Ni (19 %) av de merkede individene skiftet vinterområde (mellom Murudalen og Gausdal) minst én gang i perioden 2020–2024, og skifte av vinterområde var høyest i et år med lite snø. Dette kan bety at fordelingen av vinterdyr mellom Murudalen og Gausdal påvirkes av snøforholdene, og at vintertetthet og belastningen på vinterbeitene kan variere mellom år. Det omfattende sesongtrekket og romlige variasjonen i vinterområdebruk fører til en skjev fordeling i elgrelaterte inntekter og kostnader mellom kommuner i regionen. Kommunene i nord bærer det meste av kostnader relatert til høyt beitepress og skogskader vinterstid, mens en større del av jaktuttaket skjer i kommuner lenger sør. GPS-dataene viser at opptil 75 % av merkelgen i nord trekker ut av kommunen på våren og returnerer først sent på høsten eller tidlig på vinteren, etter at jakta er gjennomført. Reell vintertetthet kan dermed være 3–4 ganger høyere enn elgtettheten under jakta i nord, og vil i enkelte år overstige den beregnede ernæringsmessige bæreevnen. Det faktum at tettheten og beitetrykket er større i vinterområdene enn i sommerområdene og der elgen befinner seg største delen av jakta kan medvirke til at bestanden holdes på et for høyt nivå i regionen. Ettersom kun et fåtall områder opplever svært høyt beitetrykk, vil mange av kommunene som hovedsakelig huser trekkelgen sommerstid ha liten grunn til å redusere sin del av bestanden. Høye bestandstettheter over tid kan imidlertid få konsekvenser også for elgen i sør da disse for en stor del befinner seg i de nordlige kommunene vinterstid. Dette kan ha bidratt til at elgens bestandskondisjon i regionen har svekket seg over tid. Åringsvektene har for eksempel falt med om lag 10–15 % de siste 15 årene, og kalverekrutteringen har vist en tydelig nedgang. En slik utvikling samsvarer med tetthetsavhengige mekanismer, men også med pågående klimaendringer og romlig variasjon i beitekvalitet. Jaktfelt med høyere andel jordbruksareal hadde høyere tvillingandel, noe som understøtter at mer produktive arealer gir bedre grunnlag for høy kalveproduksjon. Samlet peker dette mot en bestand der tetthet, klima og beitekvalitet virker sammen over tid, og der effektene akkumuleres i form av lavere kondisjon og redusert rekruttering. Ut fra lokalkunnskap, arkeologiske funn og tidligere radiomerkestudier var det ikke overraskende at de viktigste trekkorridorene i stor grad sammenfaller med kulturhistoriske spor etter fangstanlegg. Dette viser en lang kontinuitet i elgens trekkmønstre, der dagens trekk i stor grad følger de samme rutene som elgen har fulgt i århundrer og trolig opp til flere tusen år, og som ble utnyttet av mennesker til jakt og fangst. Særlig Espedalen og enkelte passasjer ved Dokkfløyvatnet har fungert som kanaliserende elementer på elgens sesongtrekk gjennom landskapet. Her konsentreres en stor andel av de trekkende elgene gjennom relativt trange dalfører og passasjer. Slike flaskehalser kan være særlig sårbare for inngrep, for eksempel veiutbygging, kraftutbygging, hyttefelt eller andre former for infrastruktur. Endringer i disse områdene kan få uforholdsmessig stor effekt på elgens sesongtrekk, både ved å gjøre trekket mer energikrevende og ved å øke risikoen for viltpåkjørsler og konflikter. Vi vet ikke hvor mye utbygging og menneskelig tilstedeværelse som tolereres før dette har store negative konsekvenser for elgtrekket. Fra et bevaringsperspektiv er det derfor viktig at den menneskelige arealbruken i området hensyntar elgens trekkveier og at nye inngrep ikke etableres i tilknytning til trekkorridoren. Funnene peker samlet sett på et tydelig behov for en regionalt samordnet og mer grenseoverskridende forvaltning, der jaktuttak, arealbruk, overvåking og trekkruter vurderes i sammenheng og ikke kommunevis eller hos enkeltgrunneiere. Dette kan innebære felles målsettinger for bestandsstørrelse og struktur, koordinert datainnsamling og tolkning av overvåkingsdata, og vern og tilrettelegging av sentrale trekkveier. En slik helhetlig tilnærming gir trolig bedre forutsetninger for å bevare det unike elgtrekket, opprettholde god bestandskondisjon, redusere uønskede skogskader og sikre et mer rettferdig og forutsigbart jaktuttak for kommunene i regionen.

• Peris, David; Paredes, Rosneyvic González; Borrás, Luis Araque & Andrews, Josefa Oyarzún (2026). Recuperación de la capacidad de esporulación mediante el desarrollo de nuevas cepas lanzadera. University of Valencia. Full text in Research Archive
• Peris, David & Cirer, Tania Gimena (2025). Screening de levaduras del género Saccharomyces en subproductos agroalimentarios. University of Valencia. Full text in Research Archive

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