Breakdown in Postmating Isolation and the Collapse of a Species Pair through Hybridization

@article{Behm2009BreakdownIP,
  title={Breakdown in Postmating Isolation and the Collapse of a Species Pair through Hybridization},
  author={Jocelyn E. Behm and Anthony R. Ives and Janette W. Boughman},
  journal={The American Naturalist},
  year={2009},
  volume={175},
  pages={11 - 26}
}
Species that evolved through ecological speciation and that lack intrinsic genetic incompatibilities may nonetheless be maintained by extrinsic postmating isolating barriers that impose selection against hybrids. These species, however, may be vulnerable to a breakdown in postmating isolation. Here, we investigate a model system for ecological speciation: sympatric limnetic‐benthic pairs of threespine sticklebacks. Recently, stickleback hybrid abundance in Enos Lake has increased. Given that… 
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