Gibbons primarily eat fruit, says National Geographic. They are particularly fond of figs. They supplement their fruit-based diet with a variety of plants. They also eat insects, bird eggs and small birds, says Enchanted Learning.
Gibbons forage for food during the day. They live in small family groups in tropical forests. Each family group defends a large foraging territory, primarily by putting on loud vocal displays each morning.
Gibbons are arboreal animals. They rarely leave the trees because their food is all found in or on the trees. They obtain water by sipping it out of leaves or dangling on branches over water sources. Their primary form of locomotion is brachiation, which means swinging by the arms from branch to branch, although they are capable of walking upright on their hind legs if necessary. Gibbons even sleep in the trees by wedging themselves into tree forks.
Gibbons' dependence on large areas of old-growth tropical rain forest has lead to their endangerment, says National Geographic. There are 15 species of gibbons, all found in southeast Asia. Species range in size from about 30 pounds to as small as 9 pounds. Habitat loss and hunting has reduced their numbers so most species of gibbons are considered to be critically endangered as of 2014.