Adult Siamang ape in deep contemplation with hand over its mouth
The siamang (Symphalangus syndactylus) is an arboreal black-furred gibbon native to the forests of Indonesia, Malaysia and Thailand. The largest of the gibbons, the siamang can be twice the size of other gibbons, reaching 1 m in height, and weighing up to 14 kg. The siamang is the only species in the genus Symphalangus. Two features distinguish the siamang from other gibbons. The first is that two digits on each foot—the second and third toes—are partially joined by a membrane—hence the name syndactylus, from the Ancient Greek sun-, united + daktulos, finger. The second is the large gular sac (found in both males and females of the species), which is a throat pouch which can be inflated to the size of the siamang's head, allowing it to make loud, resonating calls or songs. R_9763
Adult Siamang ape in deep contemplation with hand over its mouth
The siamang (Symphalangus syndactylus) is an arboreal black-furred gibbon native to the forests of Indonesia, Malaysia and Thailand. The largest of the gibbons, the siamang can be twice the size of other gibbons, reaching 1 m in height, and weighing up to 14 kg. The siamang is the only species in the genus Symphalangus. Two features distinguish the siamang from other gibbons. The first is that two digits on each foot—the second and third toes—are partially joined by a membrane—hence the name syndactylus, from the Ancient Greek sun-, united + daktulos, finger. The second is the large gular sac (found in both males and females of the species), which is a throat pouch which can be inflated to the size of the siamang's head, allowing it to make loud, resonating calls or songs. R_9763