Speciation by Distance in a Ring Species

@article{Irwin2005SpeciationBD,
  title={Speciation by Distance in a Ring Species},
  author={Darren E. Irwin and Staffan Bensch and Jessica H. Irwin and Trevor D. Price},
  journal={Science},
  year={2005},
  volume={307},
  pages={414 - 416}
}
Ring species, which consist of two reproductively isolated forms connected by a chain of intergrading populations, have often been described as examples of speciation despite gene flow between populations, but this has never been demonstrated. We used amplified fragment length polymorphism (AFLP) markers to study gene flow in greenish warblers (Phylloscopus trochiloides). These genetic markers show distinct differences between two reproductively isolated forms but gradual change through the… 
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