Conservation Genetics

, Volume 8, Issue 1, pp 45–56

Contrasting Levels of Variation in Neutral and Quantitative Genetic Loci on Island Populations of Moor Frogs (Rana arvalis)

Authors

    • Ecological Genetics Research Unit, Department of Biological and Environmental SciencesUniversity of Helsinki
  • José M. Cano
    • Ecological Genetics Research Unit, Department of Biological and Environmental SciencesUniversity of Helsinki
  • Pierre-André Crochet
    • Department of Animal Ecology, Evolutionary Biology CentreUppsala University
    • CNRS-UMR 5175, Centre d’Ecologie Fonctionnelle et Evolutive
  • Juha Merilä
    • Ecological Genetics Research Unit, Department of Biological and Environmental SciencesUniversity of Helsinki
ORIGINAL PAPER

DOI: 10.1007/s10592-006-9147-4

Cite this article as:
Knopp, T., Cano, J.M., Crochet, P. et al. Conserv Genet (2007) 8: 45. doi:10.1007/s10592-006-9147-4

Abstract

Reduced levels of genetic variability and a prominent differentiation in both neutral marker genes and phenotypic traits are typical for many island populations as compared to their mainland conspecifics. However, whether genetic diversity in neutral marker genes reflects genetic variability in quantitative traits, and thus, their evolutionary potential, remains typically unclear. Moreover, the phenotypic differentiation on islands could be attributable to phenotypic plasticity, selection or drift; something which seldom has been tested. Using eight polymorphic microsatellite loci and quantitative genetic breeding experiments we conducted a detailed comparison on genetic variability and differentiation between Nordic islands (viz. Gotland, Öland and Læsø) and neighbouring mainland populations of moor frogs (Rana arvalis). As expected, the neutral variation was generally lower in island than in mainland populations. But as opposed to this, higher levels of additive genetic variation (V A) in body size and tibia length were found on the island of Gotland as compared to the mainland population. When comparing the differentiation seen in neutral marker genes (F ST) with the differentiation in genes coding quantitative traits (Q ST) two different evolutionary scenarios were found: while selection might explain a smaller size of moor frogs on Gotland, the differentiation seen in tibia length could be explained by genetic drift. These results highlight the limited utility of microsatellite loci alone in inferring the causes behind an observed phenotypic differentiation, or in predicting the amount of genetic variation in ecologically important quantitative traits.

Keywords

Amphibia Genetic diversity Island F ST Q ST

Copyright information

© Springer Science+Business Media B.V. 2006