suorakäsiäinen

The suorakäsiäinen, scientifically known as the siamang (Symphalangus syndactylus), is a species of gibbon found in the forests of Malaysia, Thailand, and Indonesia. It is the largest of all gibbon species, characterized by its strikingly long arms and black fur. A distinguishing feature of the siamang is the presence of syndactyly, meaning the second and third fingers of each hand are fused together, hence the Finnish name "suorakäsiäinen" which translates to "fused-handed."

These arboreal primates are primarily found in the canopy of rainforests, where they spend most of their lives. They are known for their loud, distinctive calls, which can travel for long distances through the forest. Siamangs are social animals, typically living in small family groups consisting of a monogamous pair and their offspring. Their diet consists mainly of fruits, but they also consume leaves, flowers, and insects.

The siamang's long arms are an adaptation for brachiation, their primary mode of locomotion, allowing them to swing efficiently between trees. They possess a large, inflatable throat sac that amplifies their vocalizations. Conservation efforts are in place to protect the siamang, as their habitat is threatened by deforestation and the pet trade.