Here we follow a classification reflecting those relationships. Thus constituted, the Hominidae includes 4 genera and 5 species. Its nonhuman members are restricted to equatorial Africa, Sumatra and Borneo. Hominid fossils date to the Miocene and are known from Africa and Asia. Hominids range in weight from 48 kg to 270 kg.
Males are larger than females.
Hominids are the largest primates, with robust bodies and well-developed forearms. Their pollex and hallux are opposable except in humans, who have lost opposability of the big toe. All digits have flattened nails. No hominid has a tail, and none has ischial callosities. Numerous skeletal differences between hominids and other primates are related to their upright or semi-upright stance.