Both humans and chimpanzees are able to walk bipedally (on two legs). Chimpanzees will often do this to see further ahead, but prefer to move on all fours. Humans walk upright since infancy and have evolved bowl-shaped pelvises to support their internal organs while doing so. Chimpanzees, leaning forward during movement, do not need to support their organs with their pelvis and so have broader hips.Human feet are straight with toes at the front to help push directly ahead when walking, whereas chimpanzee feet have opposable big toes and are more like strong hands than feet. They are used for climbing and crawling, involving sideways, diagonal, or rotating movements.