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. They may make young trees sway dramatically in order to reach the next tree. On the ground orangutans walk quadrupedally with feet clenched and knuckle-walking . Bipedalism is only seen in captivity, walking with arms held upright for balance.
Groups consist of an adult female with one or two young.
Males may sometimes become nomadic and leave their native territory. A new one is generally made every day. Reproduction Menstrual cycle runs 29 to 30 days. There is no sexual swelling during estrus, but shows slightly during pregnancy. Mating is done in a hanging position.