Additional file 4: Figure S1. of A history of hybrids? Genomic patterns of introgression in the True Geese

Distribution of gene tree divergence times for all goose species. All distributions show a single peak, indicating gene flow during divergence. The divergence time of several gene trees was close to zero, suggesting low levels of recent gene flow between certain species. Final three figures represent the three subspecies of Brent Goose, which is depicted in the lower right panel. (ZIP 2715 kb)