primate, Any of more than 300 species of the order Primates, including monkeys, apes, humans, and others.
Primates are distinguished from other mammals by one or more of the following traits: unspecialized structure, specialized behaviour, a short muzzle, comparatively poor sense of smell, prehensile five-digit hands and feet possessing flat nails instead of claws, acute vision with depth perception due to forward-facing eyes, a large brain, and prolonged pre- and postnatal development. Most species bear a single young and live in troops headed by a male.
The primates are one of the most diverse orders of mammals on Earth. They include the lemurs (more than 70 species in six families), the lorises (three or more species in one subfamily), the tarsiers (six or more species in one family), the New World monkeys (almost 100 species in five families), the Old World monkeys (more than 100 species in one family), and the apes and humans (about 20 species in two families).
The oldest known fossil remains of primates are about 60 million years old.