Many types of birds — such as hummingbirds, peacocks and parrots — are vividly colorful, but birds-of-paradise are especially flamboyant with hues of emerald, lemon, cobalt and ruby. Now, research has ...

image: 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 led by Princeton's ...

Structures and functions of bird’s eye. (a) Bird vision. (b) Deep central fovea and four types of cones. (c) Foveated vision and tetrachromatic vision. The eyes of raptors such as eagles can ...

Breakthroughs, discoveries, and DIY tips sent every weekday. Terms of Service and Privacy Policy. Parrots, toucans, and other brightly colored tropical birds are ...

Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. Many types of birds ...