Orangutan, a species of pongidae, i

Orangutan, a species of pongidae, is an ape with long reddish hair that comes from Broneo and Sumatra an is able to walk upright in trees by using two arms to keep balance. Since the ape, human, and other primates have the same ancestors called Amphipithecus, we can reach the conclusion that, instead of the past hypothesis that humans learned how to walk upright in grassland, they were able to walk upright long before they arrived in grassland.