Postglacial dispersal patterns and mitochondrial genetic structure of the Pyrenean desman (Galemys pyrenaicus) in the northwestern region of the Iberian Peninsula

• Published in: Ecology and evolution Vol. 7; no. 12; pp. 4486 - 4495
• Main Authors: Querejeta, Marina, Fernández‐González, Angel, Romero, Rafael, Castresana, Jose
• Format: Journal Article
• Language: English
• Published: England John Wiley & Sons, Inc 01-06-2017; Wiley Open Access; John Wiley and Sons Inc
• Subjects: Animal genetics; Aquatic ecosystems; Basins; Biological evolution; Colonization; Corridors; Deoxyribonucleic acid; Dispersal; Dispersion; DNA; Ecological conditions; Galemys pyrenaicus; genetic diversity; Genetic structure; Genetics; Holocene; Iberian Peninsula; isolation‐by‐distance; Life Sciences; Mammals; Mitochondrial DNA; Nucleotide sequence; Original Research; Phylogeny; Populations and Evolution; River networks; Rivers; Species; Streams; Terrestrial environments; Iberian Peninsula; Iberian Peninsula; genetic diversity; dispersal; Galemys pyrenaicus; isolation‐by‐distance; mitochondrial DNA
• ISSN: 2045-7758; 2045-7758
• DOI: 10.1002/ece3.3034

The genetic structure of small semiaquatic animals may be influenced by dispersal across both rivers and land. The relative importance of these two modes of dispersal may vary across different species and with ecological conditions and evolutionary periods. The Pyrenean desman (Galemys pyrenaicus) is an endemic mammal of the Iberian Peninsula with a strong phylogeographic structure and semiaquatic habits, thus making it an ideal model to study the effects of river and overland dispersal on its genetic structure. Thanks to different types of noninvasive samples, we obtained an extensive sampling of the Pyrenean desman from the northwestern region of the Iberian Peninsula and sequenced two mitochondrial DNA fragments. We then analyzed, using an isolation‐by‐distance approach, the correlation between phylogenetic distances and geographical distances measured along both river networks and land to infer the relative importance of river and overland dispersal. We found that the correlations in the whole area and in a large basin were consistent with an effect of overland dispersal, which may be due to the postglacial colonization of new territories using terrestrial corridors and, possibly, a more extensive fluvial network that may have been present during the Holocene. However, in a small basin, likely to be less influenced by the impact of ancient postglacial dispersal, the correlations suggested significant overall effects of both overland and river dispersal, as expected for a semiaquatic mammal. Therefore, different scales and geographical regions reflect different aspects of the evolutionary history and ecology of this semiaquatic species using this isolation‐by‐distance method. The results we obtained may have crucial implications for the conservation of the Pyrenean desman because they reinforce the importance of interbasin dispersal for this species in the studied area and the need to protect the whole riverine ecosystem, including rivers, upland streams and terrestrial corridors between basins.
We studied the postglacial dispersal patterns of the Pyrenean desman, an endemic semiaquatic mammal of the Iberian Peninsula, using an isolation‐by‐distance approach in which we analyzed the correlation between phylogenetic distances and geographical distances measured along both river networks and land. We found that the correlations in the whole area and in a large basin were consistent with an effect of overland dispersal, which may be due to the postglacial colonization of new territories using interbasin corridors. However, in a small basin, likely to be less influenced by the impact of ancient postglacial dispersal, the correlations suggested a significant effect of both overland and river dispersal, as expected for a semiaquatic mammal.