Any of about 12 primarily Asian species of omnivorous, diurnal monkeys (genus Macaca) with cheek pouches for carrying food. Some species have long tails, some have short tails, and some have none. Males are 16–28 in. (41–70 cm) long (excluding the tail) and weigh 12–40 lb (5.5–18 kg). Troops live in mountains and lowlands and along shores. The rhesus monkey (M. mulatta) has been important to medical and psychological research. Malays train pig-tailed macaques (M. nemestrina) to pick coconuts. Seealso Barbary ape; bonnet monkey; Celebes black ape.
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Barbary macaque (Macaca sylvana).
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The macaques constitute a genus (Macaca, /məˈkækə/) of Old World monkeys of the subfamily Cercopithecinae.
Aside from humans (genus Homo), the macaques are the most widespread primate genus, ranging from northern Africa to Japan. Twenty-two macaque species are currently recognised, and they include some of the monkeys best known to non-zoologists, such as the Rhesus Macaque (as the Rhesus Monkey), Macaca mulatta, and the Barbary Macaque (as the Barbary Ape), M. sylvanus, a colony of which lives on the Rock of Gibraltar. Although several species lack tails, and their common names therefore refer to them as apes, these are true monkeys, with no greater relationship to the true apes than any other Old World monkeys.
Several species of macaque are used extensively in animal testing.
In the late 1990s it was discovered that nearly all (about 90%) pet and captive macaques are carriers of the herpes-B virus. This virus is harmless to macaques, but infections of humans, while rare, are potentially fatal. A 2005 University of Toronto study showed that urban performing macaques also carried simian foamy virus, suggesting they could be involved in the species-to-species jump of similar retroviruses to humans.