David Sibley: How reflected light gives birds their most vivid plumage

The brilliant yellow, orange, and red that you seen on many birds are not just for decoration; the colors send an important message about the health of each individual. The colors are products of pigments known as carotenoids, which a bird gains from its diet and uses in its immune system. Consequently, a bird showing … Read More "David Sibley: How reflected light gives birds their most vivid plumage" Originally Published March 11, 2016