title: Phylogeography and conservation genetics of the common wall lizard, Podarcis muralis, on islands at its northern range.
abstract: Populations at range limits are often characterized by lower genetic diversity, increased genetic isolation and differentiation relative to populations at the core of geographical ranges. Furthermore, it is increasingly recognized that populations situated at range limits might be the result of human introductions rather than natural dispersal. It is therefore important to document the origin and genetic diversity of marginal populations to establish conservation priorities. In this study, we investigate the phylogeography and genetic structure of peripheral populations of the common European wall lizard, Podarcis muralis, on Jersey (Channel Islands, UK) and in the Chausey archipelago. We sequenced a fragment of the mitochondrial cytochrome b gene in 200 individuals of P. muralis to infer the phylogeography of the island populations using Bayesian approaches. We also genotyped 484 individuals from 21 populations at 10 polymorphic microsatellite loci to evaluate the genetic structure and diversity of island and mainland (Western France) populations. We detected four unique haplotypes in the island populations that formed a sub-clade within the Western France clade. There was a significant reduction in genetic diversity (HO, HE and AR) of the island populations in relation to the mainland. The small fragmented island populations at the northern range margin of the common wall lizard distribution are most likely native, with genetic differentiation reflecting isolation following sea level increase approximately 7000 BP. Genetic diversity is lower on islands than in marginal populations on the mainland, potentially as a result of early founder effects or long-term isolation. The combination of restriction to specific localities and an inability to expand their range into adjacent suitable locations might make the island populations more vulnerable to extinction.
authors: Edward Grey Institute, Department of Zoology, University of Oxford, OX1 3PS, Oxford, United Kingdom.
authors: Sozos
authors: S
authors: Michaelides
authors: States of Jersey, Department of the Environment, Howard Davis Farm, La Route de la Trinite, Trinity, Jersey, JE3 5JP, Channel Islands, United Kingdom.
authors: Nina
authors: N
authors: Cornish
authors: Durrell Institute of Conservation and Ecology (DICE), School of Anthropology and Conservation, University of Kent, Canterbury, Kent, CT2 7NR, United Kingdom.
authors: Richard
authors: R
authors: Griffiths
authors: Durrell Institute of Conservation and Ecology (DICE), School of Anthropology and Conservation, University of Kent, Canterbury, Kent, CT2 7NR, United Kingdom.
authors: Jim
authors: J
authors: Groombridge
authors: Edward Grey Institute, Department of Zoology, University of Oxford, OX1 3PS, Oxford, United Kingdom.
authors: Natalia
authors: N
authors: Zajac
authors: International Institute for Culture, Tourism and Development, London Metropolitan University, 277-281, Holloway Road, London, N7 8HN, United Kingdom.
authors: Graham J
authors: GJ
authors: Walters
authors: Station d'Ecologie Expérimentale de Moulis, CNRS, 09200, Saint-Girons, France.
authors: Fabien
authors: F
authors: Aubret
authors: Edward Grey Institute, Department of Zoology, University of Oxford, OX1 3PS, Oxford, United Kingdom; School of Biological Sciences, University of Tasmania, PO Box 55, Hobart, Tas, 7001, Australia.
authors: Geoffrey M
authors: GM
authors: While
authors: Edward Grey Institute, Department of Zoology, University of Oxford, OX1 3PS, Oxford, United Kingdom; Department of Biology, Lund University, Sölvegatan 37, SE 223 62, Lund, Sweden.
authors: Tobias
authors: T
authors: Uller
mesh_terms: D000818:Animals; D005060:Europe; D014644:Genetic Variation; D005828:Genetics, Population; D005838:Genotype; D008116:Lizards / Q000235:genetics*; D058974:Phylogeography