Anders Isaksen

• Isaksen, Anders; Nachtigall, Pedro Gabriel; Araya, Robin Aasegg; Beh, Jia Hao; Robinson, Samuel D. & Hansen, Thomas Fredrik [Show all 7 contributors for this article] (2025). Genome of the green-head ant, Rhytidoponera metallica, reveals mechanisms of toxin evolution in a genetically hyper-diverse eusocial species. Genome Biology. ISSN 1474-7596. 26(1). doi: 10.1186/s13059-025-03777-2. Full text in Research Archive Show summary

  Background While ants are textbook examples of eusocial animals in which altruistic behavior is maintained through kin selection, several ants form genetically diverse colonies that challenge this concept. One example is the Australian green-head ant (Rhytidoponera metallica) whose colonies harbor such extreme genetic variation that they have been speculated to represent an unstable form of eusociality. Yet, R. metallica is among the most successful ants on the Australian subcontinent. This success has been hypothesized to be partly due to the diverse venoms harbored within each colony. However, the genomic basis and evolutionary scenarios that maintain this toxin diversity remain unknown. Results To examine toxin genomic architecture, quantify individual-level genetic variation, and identify both proximate and ultimate mechanisms that have facilitated the toxin diversity in R. metallica, we generate a high-quality draft genome from a single worker. Most ectatotoxin genes are in clusters that contain evidence of multiple, complex gene-family expansions, some of which are likely explained by the presence of transposable elements. We also show that toxin regions of the genome exhibit elevated genetic variation despite being under strong selection and that this variation can translate to phenotypic diversity through toxin alleles with different functional properties. Conclusions Taken together, our results point to classical gene duplication and diversification as the main evolutionary mechanism by which the main toxin family in ant venoms evolves, suggest toxin-gene functional diversification under frequency-dependent selection maintains colony-level venom hypervariability in R. metallica, and provide new insight into the role of multi-level selection in eusocial animals.

• Pélabon, Christophe; Agudelo-Cantero, Gustavo Adolfo; Ajoy, Yimen Gerardo Araya; Bolstad, Geir Hysing; Cheng, Changde & Galis, Frietson [Show all 26 contributors for this article] (2025). Evolvability: progress and key questions. BioScience. ISSN 0006-3568. 75(12), p. 1057–1057. doi: 10.1093/biosci/biaf111. Full text in Research Archive Show summary

  Since the 1990s, evolutionary biologists have recognized the importance of explaining the ability of biological systems to evolve and how this ability itself evolves. This recognition of the need to explain evolvability emerged from an awareness that the kind and the amount of heritable variation available for natural selection require explanation. The concept of evolvability is now the focus of many research programs in diverse subdisciplines within evolutionary biology. In the present article, we first review and synthesise progress made in evolvability research. We then present key questions to set an agenda for future research on evolvability, identify challenges to answer these questions, and discuss opportunities to apply results from the evolvability research to conservation biology.

• Halbritter, Aud Helen; Vandvik, Vigdis; Cotner, Sehoya Harris; Farfan-Rios, William; Maitner, Brian S. & Michaletz, Sean T. [Show all 62 contributors for this article] (2024). Plant trait and vegetation data along a 1314 m elevation gradient with fire history in Puna grasslands, Perú. Scientific Data. 11. doi: 10.1038/s41597-024-02980-3. Full text in Research Archive Show summary

  Alpine grassland vegetation supports globally important biodiversity and ecosystems that are increasingly threatened by climate warming and other environmental changes. Trait-based approaches can support understanding of vegetation responses to global change drivers and consequences for ecosystem functioning. In six sites along a 1314 m elevational gradient in Puna grasslands in the Peruvian Andes, we collected datasets on vascular plant composition, plant functional traits, biomass, ecosystem fluxes, and climate data over three years. The data were collected in the wet and dry season and from plots with different fire histories. We selected traits associated with plant resource use, growth, and life history strategies (leaf area, leaf dry/wet mass, leaf thickness, specific leaf area, leaf dry matter content, leaf C, N, P content, C and N isotopes). The trait dataset contains 3,665 plant records from 145 taxa, 54,036 trait measurements (increasing the trait data coverage of the regional flora by 420%) covering 14 traits and 121 plant taxa (ca. 40% of which have no previous publicly available trait data) across 33 families.

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