Why does a Caribbean angelfish sometimes resemble its Indo-Pacific cousin, even though they have never lived in the same ocean? Why do coral reefs harbor such a wide range of stripes, spots and ...

The bright colors of the sponges have a meaning tied to their intended use. Here's a guide to sponge colors and when to use each type. David lives in Brooklyn where he's spent more than a decade ...

Many mammals have fur the color of brown and black. Why don't they have more exotic colors, like purple and neon pink?