No neck is visible. Muzzles are massive, rounded and protecting. This enables the male's voice to carry half a mile. The orangutan has long arms and short legs. Legs may go at right angles to the body for better maneuverability in the trees.
Hands are long, slender and prehensile with curved phalanges.
The thumb is short and set close to the wrist. Feet are hook-like with a reduced big toe similar to hands. Fingers and toes show strongly curved nails. Behavior Brachiation in trees involves the use of all limbs, with the feet as effective as hands. Movement is cautious in adults with no leaping or jumping.