Some species responded successfully to prehistoric changes in climate [1,2], while others failed to adapt and became extinct [3]. The factors that determine successful climate adaptation remain poorly understood. We constructed a reference genome and studied physiological adaptations in the Alpine marmot (Marmota marmota), a large ground-dwelling squirrel exquisitely adapted to the "ice-age" climate of the Pleistocene steppe [4,5]. Since the disappearance of this habitat, the rodent persists in large numbers in the high-altitude Alpine meadow [6,7]. Genome and metabolome showed evidence of adaptation consistent with cold climate, affecting white adipose tissue. Conversely, however, we found that the Alpine marmot has levels of genetic variation that are among the lowest for mammals, such that deleterious mutations are less effectively purged. Our data rule out typical explanations for low diversity, such as high levels of consanguineous mating, or a very recent bottleneck. Instead, ancient demographic reconstruction revealed that genetic diversity was lost during the climate shifts of the Pleistocene and has not recovered, despite the current high population size. We attribute this slow recovery to the marmot's adaptive life history. The case of the Alpine marmot reveals a complicated relationship between climatic changes, genetic diversity, and conservation status. It shows that species of extremely low genetic diversity can be very successful and persist over thousands of years, but also that climate-adapted life history can trap a species in a persistent state of low genetic diversity.
1.Univ Sheffield, Dept Anim & Plant Sci, Sheffield S10 2TN, S Yorkshire, England 2.Bielefeld Univ, Dept Anim Behav, D-33501 Bielefeld, Germany 3.Francis Crick Inst, Mol Biol Metab Lab, 1 Midland Rd, London NW1 1AT, England 4.Univ Liverpool, Inst Integrat Biol, Ctr Genom Res, Biosci Bldg,Crown St, Liverpool L69 7ZB, Merseyside, England 5.Max Planck Inst Mol Genet, Sequencing Core Facil, Ihnestr 73, D-14195 Berlin, Germany 6.Univ Angers, IRHS, INRA, Agrocampus Ouest,SFR QuaSaV 4207, F-49071 Beaucouze, France 7.Univ Bordeaux, INRA, BIOGECO, 69 Route Arcachon, F-33612 Cestas, France 8.Leibniz Inst Freshwater Ecol & Inland Fisheries, Dept Ecophysiol & Aquaculture, D-12587 Berlin, Germany 9.Univ Cambridge, Dept Biochem, 80 Tennis Court Rd, Cambridge CB2 1GA, England 10.Univ Cambridge, Cambridge Syst Biol Ctr, 80 Tennis Court Rd, Cambridge CB2 1GA, England 11.Univ Leeds, Leeds Inst Cardiovasc & Metab Med, Leeds LS2 9JT, W Yorkshire, England 12.Med Univ Innsbruck, Div Med Biochem, A-6020 Innsbruck, Austria 13.EMBL, D-69117 Heidelberg, Germany 14.Earlham Inst, Norwich Res Pk, Norwich NR4 7UZ, Norfolk, England 15.Quadram Inst, Gut Hlth & Microbes Programme, Norwich Res Pk, Norwich NR4 7UQ, Norfolk, England 16.Inst Avian Res, D-26386 Wilhelmshaven, Germany 17.Charite, Dept Biochem, Charitepl 1, D-10117 Berlin, Germany 18.Chalmers Univ Technol, Dept Biol & Biol Engn, S-41296 Gothenburg, Sweden 19.KTH Royal Inst Technol, Sci Life Lab, S-17165 Stockholm, Sweden 20.Max Delbruck Ctr Mol Med, D-13092 Berlin, Germany 21.Mol Med Partnership Unit, D-69120 Heidelberg, Germany 22.Univ Lyon, F-69000 Lyon, France 23.Univ Lyon 1, CNRS, UMR 5558, Lab Biometrie & Biol Evolut, F-69622 Villeurbanne, France 24.Univ Cambridge, Dept Genet, Cambridge CB2 3EH, England
Recommended Citation:
Gossmann, Toni I.,Shanmugasundram, Achchuthan,Boerno, Stefan,et al. Ice-Age Climate Adaptations Trap the Alpine Marmot in a State of Low Genetic Diversity[J]. CURRENT BIOLOGY,2019-01-01,29(10):1712-+