Migratory birds may have evolved to be lighter in color than their nonmigratory counterparts, as paler plumage absorbs less heat than darker feathers, according to a study published yesterday (December 6) in Current Biology.
Color has been co-opted by birds to aid in everything from camouflage to mate selection, but it’s not only vivid hues that have an evolutionary benefit. Prior research has shown, for instance, that birds nesting in cold climates often lay eggs that are darker, and therefore retain heat better, and many species use drab coloring or black and white contrast to blend in.
Whether color has any bearing on migration—a behavior roughly half of all bird species engage in to some extent—has rarely been studied. Two recent papers documented how great snipes (Gallinago media) and great reed warblers (Acrocephalus arundinaceus) fly at much higher altitudes during the day than at night, leading the researchers to suggest ...
