Connectivity in a pond system influences migration and genetic structure in threespine stickleback

Ecology and Evolution

Mathew Seymour¹  Katja Räsänen³  Rolf Holderegger² 

[1] Department of Aquaculture and Fish Biology, Hólar University College, 550 Skagafjörður, Iceland;Biodiversity and Conservation Biology, WSL Swiss Federal Research Institute, CH-8903 Birmensdorf, Switzerland;Department of Aquatic Ecology and Institute of Integrative Biology, EAWAG, CH-8600 Dübendorf, Switzerland

关键词: Gasterosteus aculeatus;    Iceland;    landscape genetics;    microsatellites;    periodic flooding;   

DOI  :  10.1002/ece3.476

来源: Wiley

【 摘 要 】

Abstract

Neutral genetic structure of natural populations is primarily influenced by migration (the movement of individuals and, subsequently, their genes) and drift (the statistical chance of losing genetic diversity over time). Migration between populations is influenced by several factors, including individual behavior, physical barriers, and environmental heterogeneity among populations. However, drift is expected to be stronger in populations with low immigration rate and small effective population size. With the technological advancement in geological information systems and spatial analysis tools, landscape genetics now allows the development of realistic migration models and increased insight to important processes influencing diversity of natural populations. In this study, we investigated the relationship between landscape connectivity and genetic distance of threespine stickleback (Gasterosteus aculeatus) inhabiting a pond complex in Belgjarskógur, Northeast Iceland. We used two landscape genetic approaches (i.e., least-cost-path and isolation-by-resistance) and asked whether gene flow, as measured by genetic distance, was more strongly associated with Euclidean distance (isolation-by-distance) or with landscape connectivity provided by areas prone to flooding (as indicated by Carex sp. cover)? We found substantial genetic structure across the study area, with pairwise genetic distances among populations (D_PS) ranging from 0.118 to 0.488. Genetic distances among populations were more strongly correlated with least-cost-path and isolation-by-resistance than with Euclidean distance, whereas the relative contribution of isolation-by-resistance and Euclidian distance could not be disentangled. These results indicate that migration among stickleback populations occurs via periodically flooded areas. Overall, this study highlights the importance of transient landscape elements influencing migration and genetic structure of populations at small spatial scales.

【 授权许可】

CC BY   
© 2013 The Authors. Ecology and Evolution published by Blackwell Publishing Ltd.

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