Kinship, Friendship, Sex and Aggression in Free-ranging Rhesus Monkeys is an "ethnography" of social behavior. Descended from individuals brought from India in 1938 by the comparative primate psychologist C.R. Carpenter, who anticipating WWII, foresaw the supply of monkeys for medical research being cut off. The colony is located on Cayo Santiago, a forty-acre island, 5/8 of a mile off the coast of Puerto Rico and is by now the best-studied population of nonhuman primates in the world. Following Carpenter's initial studies (1942), a detailed field study of the Cayo Santiago colony was made by...