What is most important when looking at and watching birds? The easy answer is to carefully look at the entire bird. You will ...

Color systems date back centuries, at least to Richard Waller’s 1686 Tabula colorum physiologica. Yet bird-watching hones a sharp eye for color differentiation, so Ridgway had an edge — as ...

If birds' beaks are covered in keratin, though, how is color change possible? After all, our hair and fingernails are likewise formed of keratin, and we can't change the color of either — at ...

While humans have three color cones in the retina sensitive to red, green and blue light, birds have a fourth color cone that can detect ultraviolet light. A research team trained wild ...

Metaphorically, if the birds were artists, they would use carotenoids as a broad brush to produce color patches, with melanins as a detail paint brush to produce more intricate designs.