Population Demography and Genetic Diversity in the Pleistocene Cave Lion

Characterized by considerable climatic instability, the Pleistocene was a time of changing ecological conditions that affected both plant and animal life. Glacialinterglacial cycles were irregular and created contrasting landscapes and environments in many regions over time (Hofreiter and Stewart, 2009). These regional and global changes had a profound impact on animal populations, resulting in lineage diversification, range shifts, demographic bottlenecks, and extinctions. Until recently such processes have mainly been traced through the fossil record at a morphological level. However, in the last couple of decades, the analysis of ancient DNA (aDNA) has been adding valuable information, deciphering ancient population dynamics even in the distant past (Lorenzen et al., 2011). So far, a number of extant as well as extinct animal species have been investigated using the combined tools of morphology and aDNA analysis. The results have in many instances caused revisions of long-standing theories, giving a more complex picture of how animal populations have reacted to climate change (de Bruyn et al., 2011; Hofreiter and Stewart, 2009). Generally, the model of contraction and expansion of population ranges following the glacial cycles holds true for many species (Bennett and Provan, 2008). However, contrary to the previous belief that animals tracked their habitats during range contractions, it has been shown that some populations died out completely as their environment changed (Campos et al., 2010a; Campos et al., 2010b; Dalen et al., 2007). Furthermore, species often seem to have responded in an * Stockholm University and the Swedish Museum of Natural History, Stockholm, Sweden [email protected], [email protected] † Centre for GeoGenetics, Natural History Museum of Denmark, Copenhagen, Denmark [email protected] ‡ Department of Earth Sciences, Natural History Museum, London, UK [email protected] § Durham Evolution and Ancient DNA, Archaeology Department, Durham University, Durham, UK. and Centre for GeoGenetics, Natural History Museum of Denmark, Copenhagen, Denmark [email protected] ‖ School of Biological Sciences, Durham University, South Road, Durham, UK [email protected] ¶ Palaeontology Department, Natural History Museum, London, UK [email protected] ** Swedish Museum of Natural History, Stockholm, Sweden [email protected] Corresponding author: Erik Ersmark RESEARCH PAPER