Fig. 2From: Differential introgression and the maintenance of species boundaries in an advanced generation avian hybrid zoneBar plot showing the distribution of haplotypes by transect point (nelsoni haplotypes are blue, caudacutus haplotypes are in red, and hybrid haplotypes are in gray). Each panel represents a marker, from top to bottom: ND3/ND2 (mitochondrial), RAG1 (nuclear), SLC45A2 (z-linked), and SLC30A5 (z-linked). The hybrid zone is located between sampling points 4 and 27Back to article page