These birds are olive with bright yellow throats and breasts. And their black eye mask is offset by a blurry white line that separates the face from the head. The common yellowthroat is abundant ...

Staring pale-yellow eyes set off by red orbital ring ... often dark wash basally (most heavily marked birds look dark-tailed); tail band sometimes broken subterminally by whitish marks.

Birds-of-paradise are known for their bright colours and courtship displays. Now, it turns out that many species also have body parts that fluoresce ...

Crab spiders can change from white to yellow and back again depending on their ... Kelly Colgan Azar, licensed under CC BY-ND 2.0 Adult male warblers are a richer shade of yellow than females and ...