Lighter Migratory Birds
A recent study speculates that migratory birds have lighter colored feathers because they reduce the risk of overheating (Kaspar Delhey, James Dale, Mihai Valcu, and Bart Kempenaers. Migratory birds are lighter coloured. Current Biology, 2021). They say “We found across nearly all species of birds, migratory species tend to be lighter colored than non-migratory species. …