Members of the family Hominidae, including our own species Homo sapiens, our presumed forebears Homo erectus and Homo habilis, and forms believed to be closely related called collectively the australopithecines. Many scientists now also include the African great apes – the two chimpanzees and gorilla – in the human family, rather than grouping them with the more distantly related Asian apes. The traditional way of grouping the large apes (chimpanzees, gorilla, and orang-utan) is in their own family, Pongidae. Estimates of the date of divergence of the ape and human lineages vary. The Asian apes probably branched off 8–12 million years ago and the African apes 10–5 million years ago. The stages of development in which humans diverged from ape-like ancestors and took on their present form took at least five million years. Many details remain uncertain, particularly of the relationship between the australopithecines and the Homo lineage, and the position of such remains as those found at Broken Hill, in central Zambia. Here, skeletal material, once called Rhodesian Man, is now usually referred to as Kabwe or Broken Hill Man. These finds are believed to represent a population in Africa 400,000–200,000 years ago that is transitional between late Homo erectus and early or ‘archaic’ Homo sapiens.
The first australopithecine fossil was discovered at Taung in southern Africa in 1924 and named Australopithecus africanus (southern ape of Africa). Since then, australopithecine fossils have been found in southern and eastern Africa but the relationships between the different forms are still far from clear.
Current opinion divides them into two, or perhaps three main groups that date from over 4 million to nearly 1 million years ago. One of the oldest (4–3 million years ago) and most ape-like is Australopithecus afarensis, now known from eastern African sites. This species is often linked closely to Australopithecus africanus (3–2 million years ago), best represented at Sterkfontein and Makapansgat in southern Africa. Some authorities consider both these species are human ancestors; others rule out A. africanus, some even discount both from being human ancestors. Australopithecines were clearly capable of walking upright but their brains were still ape-like. It is uncertain if they made tools.
Homo habilis (‘handy man’) refers to a group of human fossil remains found at Olduvai Gorge in Tanzania in the early 1960s; they are now known from other eastern African sites, and perhaps also from southern Africa. They date from about 2.5 million to 1.6 million years ago. Although similar in size to the contemporary australopithecines, their brains were larger, their faces more human-like, and they may have evolved into Homo erectus. They were probably the first makers of stone tools, such as the simple pebble and flake artefacts collectively called the Oldowan industry.
Homo erectus (‘upright man’), who may have been the predecessor of our own species, Homo sapiens, lived in Africa and Asia and possibly in Europe. This hominid was larger than the australopithecines and Homo habilis, with a brain approaching the size of a modern human brain. However, the facial bones remained relatively massive and the skull was long and low. One of the hallmarks of this species was a teardrop-shaped stone tool flaked on both sides, the Acheulian handaxe, which was more specialized than the Oldowan tools of Homo habilis. Homo erectus was the first member of the human lineage to control and use fire, which with its use of clothing, may have contributed to its spreading from its place of origin in tropical East Africa. It may have evolved from Homo habilis, by 1.6 million years ago. By around 1 million years ago or not long before these hominids are presumed to have begun the travels that took them as far as China (Peking Man) and Indonesia (Java Man). The last representatives disappeared 400,000–200,000 years ago.
Subjects: World History.