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Molecular evidence for ecological speciation in tropical habitats.

ABSTRACT: Recent research on rainforest speciation has highlighted the importance of habitat variation in generating population diversification but lacks evidence of an associated reduction in gene flow. This paper describes a study in which molecular markers were used to examine the effects of allopatric divergence and habitat on levels of gene flow in the Caribbean lizard, Anolis roquet. Three study transects were constructed to compare variation in microsatellite allele frequencies and morphology across phylogenetic and habitat boundaries in northern Martinique. Results showed reductions in gene flow to be concordant with divergent selection for habitat type. No evidence could be found for divergence in allopatry influencing current gene flow. Morphological data match these findings, with multivariate analysis showing correlation with habitat type but no grouping by phylogenetic lineage. The results support the ecological speciation model of evolutionary divergence, indicating the importance of habitats in biodiversity generation.

SUBMITTER: Ogden R

PROVIDER: S-EPMC129722 | biostudies-literature | 2002 Oct

REPOSITORIES: biostudies-literature

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Molecular evidence for ecological speciation in tropical habitats.

Ogden Rob R Thorpe Roger S RS

Proceedings of the National Academy of Sciences of the United States of America 20021007 21

Recent research on rainforest speciation has highlighted the importance of habitat variation in generating population diversification but lacks evidence of an associated reduction in gene flow. This paper describes a study in which molecular markers were used to examine the effects of allopatric divergence and habitat on levels of gene flow in the Caribbean lizard, Anolis roquet. Three study transects were constructed to compare variation in microsatellite allele frequencies and morphology acros ...[more]

PMID: 12370440

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Molecular evidence for ecological speciation in tropical habitats.

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Molecular evidence for ecological speciation in tropical habitats.

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