Animals display a dazzling variety of colors, particularly in the tropics. But even here in northern New England where wildlife diversity is comparatively limited, we enjoy a rich palette of colors and patterns. The majority of colors are produced by pigments–particles of color chemicals found within specialized cells. These include melanins, which are found in nearly all organisms and produce the earthy tones common to many animals (including humans), and carotenoids, which produce colors primarily in the red to yellow end of the spectrum (think northern cardinal and American goldfinch).
What’s surprising, however, is that pigments that produce blue coloration are all but unknown in the animal kingdom, even though we have plenty of blue-colored animals, particularly among birds, butterflies, and fish. So if it’s not pigments, what makes an animal blue? » Continue Reading.