Siamang

The siamang is a large, black-furred gibbon native to Sumatra and the Malay Peninsula. Its inflatable throat sac amplifies loud calls, and its two toes are joined by a membrane.

Gibbons: Gibbons are small, tailless apes native to the forests of South and Southeast Asia. The siamang is the largest gibbon and shares the group's long arms and arboreal life.
Gular sac: A gular sac is an expandable throat pouch used by some animals to produce or amplify sounds. The siamang inflates this sac while calling, making its vocalizations louder and more resonant.
Sumatran rainforest: The Sumatran rainforest is a tropical forest ecosystem on the Indonesian island of Sumatra. It is one of the siamang's principal habitats and is threatened by forest conversion.
Carl Linnaeus: Carl Linnaeus was a Swedish naturalist who established the modern system of biological nomenclature. Linnaeus described the siamang in the tenth edition of Systema Naturae in 1758.
Hylobatidae: Hylobatidae is the family of apes known as gibbons. This family places the siamang among lesser apes, distinct from great apes.
Gibbon song: Gibbon song is a sequence of loud, structured vocalizations produced by gibbons. Siamangs use elaborate songs to communicate across forest territories.
Malay Peninsula: The Malay Peninsula is the Southeast Asian landmass extending south from mainland Asia toward Singapore. Siamangs occupy forested parts of the peninsula as well as Sumatra.
International Union for Conservation of Nature: The International Union for Conservation of Nature is an organization that assesses species' extinction risk and supports nature conservation. Its Red List assessment records the siamang's global conservation status.
Brachiation: Brachiation is locomotion through the trees by swinging from one hand to the other. The siamang's long arms and mobile shoulders are adapted for this form of travel.
Duetting: Duetting is coordinated vocal exchange between two individuals, often in alternating or overlapping phrases. Mated siamangs commonly coordinate calls into duets that advertise pair bonds and territories.

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