title: Postglacial recolonization in a cold climate specialist in western Europe: patterns of genetic diversity in the adder (Vipera berus) support the central-marginal hypothesis.
abstract: Understanding the impact of postglacial recolonization on genetic diversity is essential in explaining current patterns of genetic variation. The central-marginal hypothesis (CMH) predicts a reduction in genetic diversity from the core of the distribution to peripheral populations, as well as reduced connectivity between peripheral populations. While the CMH has received considerable empirical support, its broad applicability is still debated and alternative hypotheses predict different spatial patterns of genetic diversity. Using microsatellite markers, we analysed the genetic diversity of the adder (Vipera berus) in western Europe to reconstruct postglacial recolonization. Approximate Bayesian Computation (ABC) analyses suggested a postglacial recolonization from two routes: a western route from the Atlantic Coast up to Belgium and a central route from the Massif Central to the Alps. This cold-adapted species likely used two isolated glacial refugia in southern France, in permafrost-free areas during the last glacial maximum. Adder populations further from putative glacial refugia had lower genetic diversity and reduced connectivity; therefore, our results support the predictions of the CMH. Our study also illustrates the utility of highly variable nuclear markers, such as microsatellites, and ABC to test competing recolonization hypotheses.
authors.affiliation: Department of Environmental Sciences, Section of Conservation Biology, University of Basel, St. Johanns-Vorstadt 10, Basel, 4056, Switzerland.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Ursenbacher
authors.affiliation: Centre d'Etudes Biologiques de Chizé, CNRS UMR 7372, Villiers en Bois, 79360, France.|Université de Poitiers, 40 Avenue du Recteur Pineau, Poitiers, 86022, France.
authors.forename: Michaël
authors.initials: M
authors.lastname: Guillon
authors.affiliation: Université de Lyon, EVS-ISTHME UMR 5600 CNRS, 6 rue Basse des Rives, Saint-Etienne Cedex 2, 42023, France.
authors.forename: Hervé
authors.initials: H
authors.lastname: Cubizolle
authors.affiliation: Centre d'Etudes Biologiques de Chizé, CNRS UMR 7372, Villiers en Bois, 79360, France.
authors.forename: Andréaz
authors.initials: A
authors.lastname: Dupoué
authors.affiliation: Département de Biologie, Université d'Ottawa, Ottawa, ON, K1N 6N5, Canada.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Blouin-Demers
authors.affiliation: Centre d'Etudes Biologiques de Chizé, CNRS UMR 7372, Villiers en Bois, 79360, France.|School of Life Sciences, Arizona State University, Tempe, AZ, 85287-4501, USA.
authors.forename: Olivier
authors.initials: O
authors.lastname: Lourdais
mesh_terms: D000483:Alleles; D000818:Animals; D001499:Bayes Theorem; D005075:Biological Evolution; D003081:Cold Climate; D005060:Europe; D014644:Genetic Variation; D005828:Genetics, Population; D018895:Microsatellite Repeats; D017422:Sequence Analysis, DNA; D017819:Viperidae / Q000235:genetics*
keywords: Approximate Bayesian Computation; glacial refugia; microsatellite; population genetic structure; snake