The vervet monkey (Chlorocebus pygerythrus), or simply vervet, is an Old World monkey of the family Cercopithecidae native to Africa. The term "vervet" is also used to refer to all the members of the genus Chlorocebus. The five distinct subspecies can be found mostly throughout Southern Africa, as well as some of the eastern countries. Vervets were introduced to Florida, Ascension Island, and Cape Verde. These mostly herbivorous monkeys have black faces and grey body hair color, ranging in length from about 50 centimetres (20 in) for males to about 40 centimetres (16 in) for females.
In addition to behavioral research on natural populations, vervet monkeys serve as a nonhuman primate model for understanding genetic and social behaviors of humans. They have been noted for having human-like characteristics, such as hypertension, anxiety, and social and dependent alcohol use. Vervets live in social groups ranging from 10 to 70 individuals, with males changing groups at the time of sexual maturity. The most significant[according to whom?] studies done on vervet monkeys involve their communication and alarm calls, specifically in regard to kin and group recognition and particular predator sightings.