Any creature of the family Hominidae (order Primates), of which only one species exists today Homo sapiens, or human beings. Extinct species of the family are indicated in fossil remains, some of which are now quite well known: Homo habilis, Homo erectus, Ardipithecus ramidus, and various species of Australopithecus. The family most closely related to the Hominidae today is the Pongidae, or anthropoid apes, including the gorilla, the chimpanzee, and the orangutan. These are believed to have diverged from a common ancestral line about 11 to about 5 million years ago. The physical characteristics that distinguish hominids from the pongids are erect posture, bipedal locomotion, rounded skulls with larger brains, small teeth (including unspecialized canines), and behavioral characteristics such as communication through language