Feather
A feather is, in birds, a complex integumentary production consisting of β-keratin. The feather is a characteristic feature of the class of birds. As the hair, the scales, the nails, the claws, the hooves, the feathers are superficial. The set of feathers, usually several thousand, forms the plumage, whose functions are to protect the body of the bird from the surrounding environment, especially against water and cold, to allow the flight, to camouflage. But it also has a social and reproductive function. The observation of a feather or of plumage may make it possible to determine the species, the sex, the age or the health of a bird. Feathers. Illustrated by Adolphe Millot in Larousse pour tous ...