The genus of primates belonging to the tribe Hominini that includes modern humans (H. sapiens, the only living representative) and various extinct species. The oldest Homo fossils are those of H. habilis and H. rudolfensis, which first appeared in Africa some 2.4 and 1.9 million years ago (mya), respectively. Both species are thought to have used simple stone tools. H. habilis appears to have been 1–1.5 m tall and had more human-like features and a larger brain than Australopithecus. H. erectus (sometimes known as H. ergaster) appeared in Africa around 1.9 mya and subsequently spread to Asia between 1.8 and 1.5 mya. Fossils of H. erectus, which was formerly called Pithecanthropus (ape man), include Java man and Peking man. They are similar to present-day humans except that there was a prominent ridge above the eyes and a receded forehead. They used crude stone tools and fire. H. erectus may also have given rise to H. heidelbergensis (represented by Heidelberg man and Boxgrove man). This latter species now contains all hominin specimens with a mixture of ‘erectus-like’ and ‘modern’ characters, dating from at least 700 000 years ago to the emergence of H. sapiens around 300 000 years ago (although evidence from Spain, Italy, and England suggests that H. heidelbergensis may date back to 1.3 mya). H. heidelbergensis is regarded as the ancestral lineage of both H. neanderthalensis (Neanderthals) and H. sapiens. In 2003 the first remains of a pygmy-sized human species, H. floresiensis, were discovered on the island of Flores, Indonesia. Fossils of this species date between 100 000 and 60 000 years ago; individuals stood about 100 cm tall; hence their nickname, the ‘Hobbit’. A fossil human ancestor, first identified in 2010 from a fragment of finger bone discovered in Denisova Cave, Siberia, is thought to belong to a new species of the genus Homo or a subspecies of H. sapiens. Sufficient DNA was contained in the bone fragment to reconstruct and sequence nearly the entire genome. The results indicate that so-called Denisovans were more closely related to Neanderthals than to ancestral modern humans, but interbred with both. See also ‘cro-magnon man’. See illustration.

Homo: timeline for main species