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 (
Migratory divides are proposed to be catalysts for speciation across a diversity of taxa. However, it is difficult to test the relative contributions of migratory behaviour vs. other divergent traits to reproductive isolation. Comparing hybrid zones with and without migratory divides offers a rare opportunity to directly examine the contribution of divergent migratory behaviour to reproductive barriers. We show that across replicate sampling transects of two pairs of barn swallow (
- PAR ID:
- 10457088
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Ecology Letters
- Volume:
- 23
- Issue:
- 2
- ISSN:
- 1461-023X
- Format(s):
- Medium: X Size: p. 231-241
- Size(s):
- p. 231-241
- Sponsoring Org:
- National Science Foundation
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