The Woolly Monkey (Lagothrix lagotricha) is an arboreal primate that inhabits the tropical rainforests of Colombia, Ecuador, Brazil, and Peru in South America. It is characterized by a wool-like, dense coat and a patch on the underside of the tail; the tail is used as an aid to grasp branches. The body is relatively robust and the tail is longer than the body. It primarily eats fruit, and also consumes leaves, flowers, and insects. It lives in multi-male/multi-female groups of about 10–70 individuals and shows a patrilineal social structure; intergroup conflicts are reported to be relatively infrequent. Populations have declined due to hunting and deforestation, and the species is classified as Vulnerable (IUCN Red List Category II).