Siamang (Symphalangus syndactylus) is a long-armed black ape that lives in trees. In general, siamang are very agile when they move up in the trees, so no predators can catch them. Siamang comes from the forest on the island of Sumatra. Siamangs do not have tails and have a less upright posture. Siamang also has a high brain development. Siamang is black, slightly reddish brown. Siamang cannot swim and is afraid of water. Siamang can live around 35-40 years.