Migratory divides are contact zones between breeding populations that use divergent
migratory routes and have been described in a variety of species. These divides are of major …

… Table S3 summarises data on the temporal and spatial patterns of migration for the birds
tracked in this study and Delmore et al. (2012). On fall migration, birds with more inland alleles …

… First, we used tracking data from Delmore and Irwin [S2] in which we tracked birds from the
center of the hybrid zone between thrushes (Pemberton and Hope, British Columbia, Canada…

Adaptation to new environments often occurs in the face of gene flow. Under these
conditions, gene flow and recombination can impede adaptation by breaking down linkage …

… geographic barriers (Delmore & Irwin 2014), and patterns of molecular variation in the hybrid
zone also suggest strong selection against hybrids (Ruegg 2008; Delmore & Irwin 2014). …

Recent technological developments allow investigation of the repeatability of evolution at the
genomic level. Such investigation is particularly powerful when applied to a ring species, in …

Detailed evaluations of genomic variation between sister species often reveal distinct
chromosomal regions of high relative differentiation (ie, “islands of differentiation” in F ST ), but …

Whole-genome sequencing projects are increasingly populating the tree of life and
characterizing biodiversity 1 , 2 , 3 – 4 . Sparse taxon sampling has previously been proposed to …

Ecologically mediated selection against hybrids, caused by hybrid phenotypes fitting poorly
into available niches, is typically viewed as distinct from selection caused by epistatic …

Seasonal migration is a complex and variable behaviour with the potential to promote
reproductive isolation. In Eurasian blackcaps (Sylvia atricapilla), a migratory divide in central …