A male Indigo Bunting in breeding plumage is a glorious symphony of shimmering blues, turquoises, and purples. But these beautiful colors are illusory: Like the iridescence of hummingbirds and the blue plumage of other species such as Eastern Bluebird,  the male Indigo Bunting owes its glorious appearance to an optical trick — the diffraction of … Continue reading Indigo Bunting