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Australopithecus africanus was an early hominid, an australopithecine, who lived between 3.3 and 2.4 million years ago in the Pliocene. In common with the older Australopithecus afarensis, A. africanus was slenderly built, or gracile, and was thought to have been a direct ancestor of modern humans. Fossil remains indicate that A. africanus was significantly more evolved than A. afarensis however, with a more human-like cranium permitting a larger brain compared to body size and more humanoid facial features.

Raymond Dart & the Taung Child

Raymond Dart was an ambitious Australian anatomist who had a great fascination with fossils, and made an important discovery in 1924 with the finding of one cranium. Dart was a professor of anatomy at Witwatersand University, Johannesburg and he was at Taung near Kimberley, South Africa when one of his colleagues spotted a few bone fragments and the cranium from the desk of a lime worker. The skull seemed like an odd ape creature sharing human traits such as eye orbits, teeth and most importantly the hole at the base of the skull over the spinal column (the foramen magnum), indicating a human-like posture. Dart then assigned the specimen the name Australopithecus africanus ("Southern Apeman of Africa"). This was the first time the word Australopithecus was assigned to any hominid. Dart claimed that the skull must have been an intermediate species between ape and man, but his claim about Taung Child was rejected by the scientific community at the time. Sir Arthur Keith, who suggested that the skull belonged to a young ape (most likely from an infant gorilla.)

Dart's theory was supported by Robert Broom, an anatomist who himself discovered the first specimen of Paranthropus robustus in 1938. Charles Darwin suggested that humans had originally evolved from Africa, but during the early 20th century most anthropologists and scientists supported the idea that Asia was the best candidate for human origins. However, the Leakey family have argued in favour of the African descent since most hominid discoveries such as the Laetoli footprints were uncovered in Eastern Africa.

Locations

Australopithecus africanus fossils are found only in South Africa. Like A. afarensis, A. africanus was a bipedal hominin, but shared a few more primitive features including the more curved fingers for tree climbing.

The one particular robust australopithecine seen as a descendent of A. africanus is Paranthropus robustus. Both P. robustus and A. africanus craniums seem very alike despite that P. robustus had heavily built features specially adapted for heavy chewing like a gorilla. Australopithecus africanus on the other hand had a cranium which quite closely resembled that of a chimpanzee, yet both their brains measure about 400cc to 500cc and probably had an ape-like intelligence. A. africanus had a pelvis that was built for slightly better bipedalism than that of A. afarensis. No stone tools of any sort have ever been found in association with australopithecines with the exception of 2.6 million year old Australopithecus garhi.

References

• BBC - Dawn of Man (2000) by Robin Mckie
• http://www.mnh.si.edu/anthro/humanorigins/ha/a_tree.html
• http://www.archaeologyinfo.com/evolution.htm

• African archaeology
• Early hominids
• Pliocene