Head and neck usually covered with feathers, but in a few instances
partially naked; bill, usually very strong, curved and very sharp; tarsi
and toes, generally strong and muscular; claws, curved, sharp; wings,
various, but usually large, and adapted to swift and vigorous flight.
Size, very much varied, body generally very compact, and organized for
strength and activity of habits, and for the destruction of living
animals. Female larger than the male.
Inhabit all parts of the world, numerous in the temperate and torrid
regions.