Capuchin Monkey, any of four species of monkey familiar as the "organ-grinder" monkey. Capuchins are found in the tropical forests of Central and South America. The name is derived from the cap of dark hair on the monkey's crown, which resembles the cowl worn by a Capuchin monk. One species also has tufts of hair on its head. The sturdy, roundheaded capuchins are about 30 to 55 cm (about 12 to 22 in) long, with a hairy, slightly prehensile tail of the same length. The tail is usually carried coiled at the tip—hence the alternative name, ringtail monkey. The monkeys are active by day and go about in troops, mainly in the tops of tall trees, feeding on fruits and small animals. There is a fairly rigid social hierarchy among both male and female capuchins. The dominant male helps to break up some fights, but other individuals also assist. Members of the troop may sound an alarm call to warn of an approaching enemy.