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   Pongo (orangutans)
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The Hominids (Hominidae) are a biological family which includes humans, extinct species of humanlike creatures and often the great apes (classifications varying considerably). Originally the group was restricted to humans and their extinct relatives, with apes (Pongo, Gorilla, and Pan) being placed in a separate family, the Pongidae. However, the Pongidae are paraphyletic, whereas most taxonomists nowadays encourage monophyletic groups. Thus many biologists consider Hominidae to include the Pongidae, or restrict the latter to the orangutan (Pongo) and extinct relatives like Gigantopithecus. Especially close human relatives are form a subfamily, the Homininae.
The exact criterion for membership in the Homininae is not clear, but usually includes the species who share more than 97% of their DNA with the modern human genome, and requires the capacity for language and for simple cultures beyond the family or band. A theory of mind giving the capacity to lie convincingly is a controversial criteria distinguishing the adult human alone among the hominids. Humans acquire this capacity at about four and a half years of age in our cultures whereas the bonobo, gorilla and chimpanzee never seem to do so. However, without the ability to test whether early members of the Homininae such as australopithecines, Homo erectus, or Neanderthals had a theory of mind, it is irrational to ignore similarities seen in their living cousins. Despite an apparent lack of real culture and significant physiological differences, some say that the orangutan may satisfy these criteria.
In 2002, a 6-7 million year old fossil skull nicknamed Toumaï by its discoverers, and formally classified as Sahelanthropus tchadensis, was discovered in Chad that is possibly the earliest hominid fossil ever found. In addition to its age, Toumaï, unlike the 3-4 million year younger Australopithecine dubbed "Lucy", has a relatively flat face without the prominent snout seen on other pre-Homo hominids. Some researchers have made the suggestion that this previously unknown species may in fact be a direct ancestor of modern humans (or at least closely related to a direct ancestor). Others contend that one fossil is not enough to make such a claim because it would overturn the conclusions of over 100 years of anthropological study. A report on this finding was published in the Journal Nature on July 11, 2002. While some scientists claim that it is merely the skull of a female gorilla, others called it the most important hominid fossil since Australopithecus.