CBER Seminar - Dr Alexandra Jansen Van Rensburg, UCL

Abstract: Predicting where and in which communities species will persist in the novel environmental conditions of coming decades depends on understanding maximum rates and patterns of evolutionary responses. However, populations and species differ in their ability to evolve in response to their changing environment, with some species maintaining or expanding their geographical ranges in response to recent climate change, while other species’ ranges are retracting rapidly. We are using a multi-species approach in UK Lepidoptera to investigate patterns of evolutionary responses to environmental change over the last century, and their effects on species’ distributions in time and space. DNA from the Natural History museum and recent UK collections has been used to generate whole genome sequencing data for populations of 20 UK Lepidoptera species (7 stable, 7 expanding, 6 contracting). Using these data we compare the pattern and extent of evolutionary change across the genome, and its effects on species’ distributions since the 1920s and across their geographical ranges today. Specifically, we ask how genetic diversity has changed over time, and how this differs between successful (stable or expanding) or vulnerable (declining) species. We also test for historical changes in population size, and evidence for selection across the genome within and among species.