The method of locomotion for Gigantopithecus is not entirely certain, as no pelvis or leg bone has been found, the only remains of Gigantopithecus discovered are teeth and mandible. A minority opinion championed by Grover Krantz holds that the mandible shape and structure suggests bipedal locomotion. The only fossil evidence of gigantopithecus -- the mandible and teeth -- are U-shaped, like bipedal humans, rather than V-shaped like the great apes. A complete fossil specimen with the pelvis and leg bones would be necessary to conclusively resolve the debate one way or the other, and have to date never been found.
Gorillas are in the same class as chimpanzees; gorillas are more closely related to humans and chimpanzees than they are orangutans.
