Summary of feral gene pool comparisons
Analyses of Bermuda’s feral chickens (and comparisons to counterparts on Kauai) revealed both unique and common features of independently feralG. gallus in the Atlantic vs. Pacific regions. Admixture analyses suggest the two feral populations originate from genetically similar colonization source(s), yet they also show asymmetrical signals of recent gene flow and selection. Bermudian feral chickens appeared to have more similarity to broiler and brown layer populations, whilst Hawaiian feral chickens had introgression from White Layer birds (or their ancestors). Hawaiian feral birds also had more introgression from Red Junglefowl (the source of domesticated chickens) in comparison to their feral Bermuda counterparts. These findings mirror what we know of the two feral population histories, with large numbers of White Layers released by the Asagi hatchery in Hawaii following tropical storms and attendant opportunity for introgression from the Red Junglefowl already present in the Hawaiian islands.