Spatial genetic structure of a small rodent in a eterogeneous landscape

• Published in: Molecular Ecology
• Main Authors: Gauffre, Bertrand, Estoup, A., Bretagnolle, Vincent, Cosson, F.
• Other Authors: Centre de Biologie pour la Gestion des Populations (UMR CBGP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université de Montpellier (UM)-Institut de Recherche pour le Développement (IRD France-Sud )-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Centre d'Études Biologiques de Chizé (CEBC), Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2008
• Subjects: clustering methods; computer simulation; gene flow; landscape genetics; microsatellites; spatial genetic structure; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; [SDE.ES]Environmental Sciences/Environmental and Society; [SDE.MCG]Environmental Sciences/Global Changes; Common vole; Microtus arvalis
• Online Access: https://hal.science/hal-00339298; https://doi.org/10.1111/j.1365-294X.2008.03950.x

Correspondance: [e-mail] International audience Gene flow in natural populations may be strongly influenced by landscape features. The integration of landscape characteristics in population genetic studies may thus improve our understanding of population functioning. In this study, we investigated the population genetic structure and gene flow pattern for the common vole, Microtus arvalis, in a heterogeneous landscape characterised by strong spatial and temporal variation. The studied area is an intensive agricultural zone of approximately 500 km2 crossed by a motorway. We used individual-based Bayesian methods to define the number of population units and their spatial borders without prior delimitation of such units. Unexpectedly, we determined a single genetic unit that covered the entire area studied. In particular, the motorway considered as a likely barrier to dispersal was not associated with any spatial genetic discontinuity. Using computer simulations, we demonstrated that recent anthropogenic barriers to effective dispersal are difficult to detect through analysis of genetic variation for species with large effective population sizes. We observed a slight, but significant, pattern of isolation by distance over the whole study site. Spatial autocorrelation analyses detected genetic structuring on a local scale, most probably due to the social organisation of the study species. Overall, our analysis suggests intense small-scale dispersal associated with a large effective population size. High dispersal rates may be imposed by the strong spatio-temporal heterogeneity of habitat quality, which characterises intensive agroecosystems.