Arctic marine mammals in a changing climate
Eline Lorenzen, from Copenhagen University in Denmark, will give a talk about "Arctic marine mammals in a changing climate – insights from ancient and modern genomes of past and present populations".
The Arctic has become one of the most contested geopolitical regions in the last decade due to loss of sea ice cover and the opening of seaways, and anticipated impacts on arctic marine ecosystems. Despite multiple studies on the impact of climate change on terrestrial mammals in the Arctic there have been no equivalent studies of marine mammals. This remarkable gap in our knowledge is due to the difficulty of assembling long-term data sets because most marine mammals die at sea. Using preliminary genome-wide data from co-distributed populations of three endemic Arctic marine mammal species - polar bears, narhwals and beluga whales - I will demonstrate how population genomics can be used to estimate the distribution of genetic variants over time and space, reconstruct demographic histories, and identify candidate genes under positive selection that have enabled these species to adapt to the extreme conditions of life in the High Arctic. I will also discuss how DNA retrieved from a unique collection of rare ancient remains spanning the past 50,000 years can be used to infer the impact of past climatic events on these species, ultimately enabling us to better forecast faunal responses to near-future projections of climate change.