What is the largest species of gibbon?

The siamang is the largest species of gibbon. This black-furred ape can weigh roughly twice as much as many other gibbons and belongs to the family Hylobatidae, commonly called the lesser apes.

Its scientific name is Symphalangus syndactylus, and it is the only living species in the genus Symphalangus. The name syndactylus refers to a distinctive feature: the second and third toes on each foot are partially joined by a membrane.

Siamangs are also famous for their enormous throat sacs. Males and females inflate these pouches to amplify their resonant calls, which help maintain pair bonds and advertise territory in dense Southeast Asian forests. Their range includes Sumatra, the Malay Peninsula, Thailand, and parts of Malaysia and Indonesia.

Although gibbons are often thought of primarily as fruit-eaters, siamangs consume many leaves as well as fruit, flowers, and insects. Habitat loss, including forest clearing for agriculture and palm oil, is a major threat.