More on Feather Pigments

In the last column, I wrote about the melanin and carotenoid pigments that birds embed in their feathers to impart color to the plumage.  Melanins are manufactured by the bird while carotenoids must be acquired from the diet. Porphyrins are a third type of feather pigment.  Porphyrins can make red, brown, green and even pink … Continue reading More on Feather Pigments