PT  - JOURNAL ARTICLE
AU  - Elizabeth S.C. Scordato
AU  - Chris C.R. Smith
AU  - Georgy A. Semenov
AU  - Yu Liu
AU  - Matthew R. Wilkins
AU  - Wei Liang
AU  - Alexander Rubtsov
AU  - Gomboobaatar Sundev
AU  - Kazuo Koyama
AU  - Sheela P. Turbek
AU  - Michael B. Wunder
AU  - Craig A. Stricker
AU  - Rebecca J. Safran
TI  - Migratory divides coincide with species barriers across replicated avian hybrid zones above the Tibetan Plateau
AID  - 10.1101/698597
DP  - 2019 Jan 01
TA  - bioRxiv
PG  - 698597
4099  - http://biorxiv.org/content/early/2019/07/11/698597.short
4100  - http://biorxiv.org/content/early/2019/07/11/698597.full
AB  - Migratory divides are proposed to be catalysts for speciation across a diversity of taxa. However, the relative contribution of migratory behavior to reproductive isolation is difficult to test. Comparing reproductive isolation in hybrid zones with and without migratory divides offers a rare opportunity to directly examine the contribution of divergent migratory behavior to reproductive barriers. We show that across replicate sampling transects of two pairs of barn swallow (Hirundo rustica) subspecies, strong reproductive isolation coincided with an apparent migratory divide spanning 20 degrees of latitude. A third subspecies pair exhibited no evidence for a migratory divide and hybridized extensively. Within migratory divides, migratory phenotype was associated with assortative mating, implicating a central contribution of divergent migratory behavior to reproductive barriers. The remarkable geographic coincidence between migratory divides and genetic breaks supports a longstanding hypothesis that the Tibetan Plateau is a substantial barrier contributing to the diversity of Siberian avifauna.