Habitat selection and ecological speciation in Galapagos warbler finches (Certhidea olivacea and Certhidea fusca).

ABSTRACT: We investigated phylogeographic divergence among populations of Galápagos warble finches. Their broad distribution, lack of phenotypic differentiation and low levels of genetic divergence make warbler finches an appropriate model to study speciation in allopatry. A positive relationship between genetic and geographical distance is expected for island taxa. Warbler finches actually showed a negative isolation by distance relationship, causing us to reject the hypothesis of distance-limited dispersal. An alternative hypothesis, that dispersal is limited by habitat similarity, was supported. We found a positive correlation between genetic distances and differences in maximum elevation among islands, which is an indicator of ecological similarity. MtDNA sequence variation revealed monophyletic

SUBMITTER: Tonnis B 

PROVIDER: S-EPMC1599867 | biostudies-literature | 2005 Apr

REPOSITORIES: biostudies-literature