Primates are a group of animals that include human beings. All primates are mammals. There are about 180 species that are members of the primate class. Besides humans, primates include great apes or gorillas, chimpanzees, bonobos, orangutans, gibbons, lemurs, aye-ayes, and macaques. Primates are classified into two main groups. The Anthropoid family includes human beings, apes, and monkeys. The other primates are in the Prosimian family. It includes aye-ayes, galagos, lemurs, lorises, pottos, and tarsiers. There are other species that have been included as prosimians, such as tree shrews, but not all scientists accept this classification.

Primates' similarities to humans have made them a frequent subject for the study of human diseases. The rhesus monkeys (Macaca mulatta), of which there are three subspecies, were used in ...