Trial lecture
The candidate will first give a trial lecture on the following topic: 'Impact of climate change on pollinators – what do we know and what do we not know?'
Time and place: Sep. 12, 2025 10:15 AM, Nucleus, Bikuben, Kristine Bonnevies hus
Research findings
Bumblebee pollination is an integral part of the temperate terrestrial ecosystem. Recent alarming declines of a range of bumblebee species have however been attributed to contemporary human activities, particularly habitat degradation and loss due to land-use change.
In this thesis, I examine the levels of dispersal, gene flow and population connectivity in three bumblebee species – Bombus lapidarius, Bombus pascuorum and Bombus consobrinus – across the anthropogenically disturbed landscapes of the Scandinavian peninsula. Despite the broad abundance and distribution of both species, we uncover significant levels of population structure in B. lapidarius and B. pascuorum. We also detect a highly divergent genomic region in B. pascuorum which we hypothesise to represent a megabase-scale chromosomal inversion, a biological feature as yet unheard of in bumblebees. Finally, we find that despite its constrained foraging ecology, the montane specialist B. consobrinus exhibits very little population structure. Measures of genetic diversity however indicate recent population contraction and may suggest restricted dispersal and gene flow between our samples and subpopulations beyond our study range. Altogether, we hope that this thesis forms a meaningful contribution to the understanding, and ultimately the safeguarding, of this fascinating and vital insect genus.
Adjudication committee
Prof. Natasha de Vere, The Natural History Museum, University of Copenhagen
Prof. Ørjan Totland, Department of Biological Sciences, University of Bergen
Prof. Leif Asbjørn Vøllestad, Department of Biosciences, University of Oslo
Chair of defense
Prof. emeritus Tore Slagsvold, Department of Biosciences, University of Oslo
Supervisors
Prof. Bastiaan Star, Department of Biosciences, University of Oslo
Head of Department/Research Anders Nielsen, Norwegian Institute of Bioeconomy Research (Nibio)
Senior Research Scientist Markus Sydenham, Norwegian Institute for Nature Research (NINA)