Serial population extinctions in a small mammal indicate Late Pleistocene ecosystem instability

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 109; no. 50; pp. 20532 - 20536
• Main Authors: Brace, Selina, Palkopoulou, Eleftheria, Dalén, Love, Lister, Adrian M, Miller, Rebecca, Otte, Marcel, Germonpré, Mietje, Blockley, Simon P. E, Stewart, John R, Barnes, Ian
• Format: Journal Article Web Resource
• Language: English
• Published: United States National Academy of Sciences 11.12.2012; National Acad Sciences
• Subjects: Animal populations; Animals; Archaeology; Archéologie; Arts & humanities; Arts & sciences humaines; Arvicolinae - classification; Arvicolinae - genetics; Biodiversity; Biological Sciences; Climate; Climate Change; Climate models; Diversity of life; DNA; DNA, Mitochondrial - genetics; Ecosystem; ecosystems; Endangered & extinct species; Environmental changes; Europe; Evolution, Molecular; Extinct species; extinction; Extinction, Biological; fauna; Fossils; Genetic diversity; genetic variation; Genetics & genetic processes; Génétique & processus génétiques; humans; Keystone species; Life sciences; Livets mångfald; Mammals; Mass extinctions; megafauna; Mitochondrial DNA; modelling; Molecular Sequence Data; Nonnative species; palaeoclimate; palaeogenetics; Paleobiology; Paleoclimatology; Paleontology; Phylogeny; Pleistocene; Population Dynamics; Radiocarbon dating; Recolonization; Sciences du vivant; small mammals; Species; Species diversity; Species extinction; Steppes; Systematic Zoology; Tundra; zoologisk systematik och evolutionsforskning; Europe
• ISSN: 0027-8424; 1091-6490; 1091-6490
• DOI: 10.1073/pnas.1213322109

The Late Pleistocene global extinction of many terrestrial mammal species has been a subject of intensive scientific study for over a century, yet the relative contributions of environmental changes and the global expansion of humans remain unresolved. A defining component of these extinctions is a bias toward large species, with the majority of small-mammal taxa apparently surviving into the present. Here, we investigate the population-level history of a key tundra-specialist small mammal, the collared lemming (Dicrostonyx torquatus), to explore whether events during the Late Pleistocene had a discernible effect beyond the large mammal fauna. Using ancient DNA techniques to sample across three sites in North-West Europe, we observe a dramatic reduction in genetic diversity in this species over the last 50,000 y. We further identify a series of extinction-recolonization events, indicating a previously unrecognized instability in Late Pleistocene small-mammal populations, which we link with climatic fluctuations. Our results reveal climate-associated, repeated regional extinctions in a keystone prey species across the Late Pleistocene, a pattern likely to have had an impact on the wider steppe-tundra community, and one that is concordant with environmental change as a major force in structuring Late Pleistocene biodiversity.