Hybrid zones are geographic regions where isolating barriers between divergent populations are challenged by admixture. Identifying factors that facilitate or inhibit hybridization in sympatry can illuminate the processes that maintain those reproductive barriers. We analysed patterns of hybridization and phenotypic variation across two newly discovered hybrid zones between three subspecies of barn swallow (
Gene flow is thought to impede genetic divergence and speciation by homogenizing genomes. Recent theory and research suggest that sufficiently strong divergent selection can overpower gene flow, leading to loci that are highly differentiated compared to others. However, there are also alternative explanations for this pattern. Independent evidence that loci in highly differentiated regions are under divergent selection would allow these explanations to be distinguished, but such evidence is scarce. Here, we present multiple lines of evidence that many of the highly divergent
- NSF-PAR ID:
- 10091205
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Molecular Ecology
- Volume:
- 28
- Issue:
- 7
- ISSN:
- 0962-1083
- Page Range / eLocation ID:
- p. 1709-1729
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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