title: Looking into the past - the reaction of three grouse species to climate change over the last million years using whole genome sequences.
abstract: Tracking past population fluctuations can give insight into current levels of genetic variation present within species. Analysing population dynamics over larger timescales can be aligned to known climatic changes to determine the response of species to varying environments. Here, we applied the Pairwise Sequentially Markovian Coalescent (psmc) model to infer past population dynamics of three widespread grouse species; black grouse, willow grouse and rock ptarmigan. This allowed the tracking of the effective population size (Ne ) of all three species beyond 1 Mya, revealing that (i) early Pleistocene cooling (~2.5 Mya) caused an increase in the willow grouse and rock ptarmigan populations, (ii) the mid-Brunhes event (~430 kya) and following climatic oscillations decreased the Ne of willow grouse and rock ptarmigan, but increased the Ne of black grouse and (iii) all three species reacted differently to the last glacial maximum (LGM) - black grouse increased prior to it, rock ptarmigan experienced a severe bottleneck and willow grouse was maintained at large population size. We postulate that the varying psmc signal throughout the LGM depicts only the local history of the species. Nevertheless, the large population fluctuations in willow grouse and rock ptarmigan indicate that both species are opportunistic breeders while black grouse tracks the climatic changes more slowly and is maintained at lower Ne . Our results highlight the usefulness of the psmc approach in investigating species' reaction to climate change in the deep past, but also that caution should be taken in drawing general conclusions about the recent past.
authors.affiliation: Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, Uppsala, SE-75236, Sweden.
authors.forename: Radoslav
authors.initials: R
authors.lastname: Kozma
authors.affiliation: Faculty of Industrial Engineering, Mechanical Engineering and Computer Science, University of Iceland, Reykjavik, 107, Iceland.|deCODE Genetics/Amgen, Reykjavik, Iceland.
authors.forename: Páll
authors.initials: P
authors.lastname: Melsted
authors.affiliation: The Icelandic Institute of Natural History, Borgir v. Nordurslod, Akureyri, 600, Iceland.|Department of Natural Resource Sciences, University of Akureyri, Borgir vid Nordurslod, Akureyri, 600, Iceland.|Biomedical Center, University of Iceland, Vatnsmýrarvegur 16, Reykjavik, 101, Iceland.
authors.forename: Kristinn P
authors.initials: KP
authors.lastname: Magnússon
authors.affiliation: Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, Uppsala, SE-75236, Sweden.
authors.forename: Jacob
authors.initials: J
authors.lastname: Höglund
mesh_terms: D000818:Animals; D001110:Arctic Regions; D005075:Biological Evolution; D057231:Climate Change; D046094:Galliformes / Q000145:classification / Q000235:genetics*; D014644:Genetic Variation; D059645:Mutation Rate; D011156:Population Density; D011157:Population Dynamics
keywords: Pleistocene; Tetraoninae; climate change; effective population size; pairwise sequentially Markovian coalescent