How bird feathers produce color -- it's all about beer (sort of)

[Catshrink]

Bird Feathers Produce Color Through Structure Similar to Beer Foam


Prum and Dufresne discovered that the nanostructures that produce some birds’ brightly colored plumage, such as the blue feathers of the male Eastern Bluebird, have a sponge-like structure. (Photo: Ken Thomas)

New Haven, Conn. — Some of the brightest colors in nature are created by tiny nanostructures with a structure similar to beer foam or a sponge, according to Yale University researchers.

Most colors in nature—from the color of our skin to the green of trees—are produced by pigments. But the bright blue feathers found in many birds, such as Bluebirds and Blue Jays, are instead produced by nanostructures. Under an electron microscope, these structures look like sponges with air bubbles.

More here:

http://opa.yale.edu/news/article.aspx?id=6559

Hm... I will be investigating this more.

[mike_c]

1. this is common in insects....

See Tyndell blue, for example. Iridescence is also structural color, caused by wavelength interaction with multiple thin layers of integument. Other colors, including white, can result from light scattering at specific wavelengths by granular inclusions in the integument. There are LOTS of examples of structural color among insects!