Birds in living color

Natural History, April, 2002 by B. Adam

I enjoyed reading J. Albert C. Uy's article on bowerbirds ("Say It With Bowers," 3/02) but was surprised that the author states that male Vogelkops sort the objects around the bowers by color. I thought color vision was an exclusive trait of primates.

B. Adam
New York, New York

J. ALBERT C. UY REPLIES: Color vision is not restricted to primates. In fact, various other animals have better color vision than primates. While the males of some New World primates have only two types of cones in their retinas, in general primates have three, allowing them to see color in the short, medium, and long wavelengths. Other animals with three cone types include some freshwater fish, diurnal reptiles and amphibians, crustaceans, many insects, and certain spiders. Birds, turtles, some freshwater fish, and butterflies possess four cone types in their retinas, enabling them to see in the ultraviolet range as well.

THE EDITORS ADD: For more on color and vision, read "Seeing Red ... and Yellow ... and Green ... and," also in our 3/02 issue.