OLD WORLD MONKEYS FACTS
Old World monkeys are divided into the leaf-eating monkeys (including langurs [lang-GURZ] and colobus and proboscis monkeys) and the cheek-pouched monkeys (including macaques [muh-KOCKS] and mandrills). Most have subdued dark colorations with lighter undersides. Some, such as mandrills, have spectacular color combinations. All species have forward-facing eyes and short snouts. The buttocks have two hardened pads for prolonged sitting. Most have long tails. Leafeaters have a four-chamber stomach for digesting their main diet of plants. The cheek pouches are used for storing food to be safely eaten in trees.
Leaf monkeys are found in Asia and Southeast Asia, except for the colobus monkeys. Cheek-pouched monkeys are found in Africa, including the Barbary macaque. All other macaques are found in Southeast Asia.
OLD WORLD MONKEYS HABITAT
Old World monkeys live in virtually all land habitats, including grasslands, open dry forests, dense evergreen forests, mangroves, swamps, and forests along rivers. Some live near humans.
OLD WORLD MONKEYS DIET
Leaf monkeys eat mainly leaves. Cheek-pouched monkeys consume fruits, seeds, insects, and occasionally young leaves.
BEHAVIOR AND REPRODUCTION
Old World monkeys are diurnal (active during the day). Most are arboreal (treedwelling), traveling on all fours. They can also leap, using the tail for balance. Some species use some brachiation (brake-ee-AYshun, a type of locomotion in which an animal swings below branches using its arms. Social groups vary in size. Larger groups may split into subgroups when foraging. They are polygynous (puh-LIH-juh-nus), with males having several partners. Females have single births. Young females leave their birthplace, while young males stay with the group.
OLD WORLD MONKEYS AND PEOPLE
Old World monkeys are hunted for food. Some species are used in medical research.
The World Conservation Union (IUCN) lists five species as Critically Endangered, facing an extremely high risk of extinction, due to hunting, as well as habitat loss and degradation from agriculture, logging, and other human activities. These are the eastern red colobus, the Tonkin snub-nosed monkey, the Delacour langur, the white-headed langur, and the Mentawai macaque. Twenty-two species are classified as Endangered, facing a very high risk of extinction in the wild; seventeen are Vulnerable, facing a high risk of extinction in the wild; and twenty are Near Threatened, not currently threatened, but could become so.