Australopithecus is a genus of ancient hominid fossils that first came to our knowledge in 1924 when dicovered by South African anatomy professor Rayomnd Dart. He originally named his new found species "Australopithecus Africanus" meaning "the southern ape of Africa." Dart made his dicovery upon receiving the skull of a young child which he noticed had teeth shaped differently from those of apes and ressembled rather the structure of modern human teeth. However, the brain of the child, even if it had reached maturity couldn't have been larger than that of a gorilla. Nevertheless, Dart still believed that he had found the remains of an ancient ancestor of the human race, although scientists remained unconvinced until the later discovery of adult specimens by Scottish paleontologist Robert Broom. His fossils included pieces of the pelvis and thigh bones, teahcing Broom that Australopithecus was an erect biped, one of the most important characteristics attritbuted to hominids (humanlike or related creatures).

Many more discoveries were to be made in regards to australopithecines including the realization that there were two different species of Australopithecus, the A. Africanus and its heavier, larger counterpart, A. robustus. In 1959, a skull was found that belonged to a speices even more massive than the robust Australopithecus and was named the A. boisei. In 1974 in Ethiopia, ancient australopitecine bones that predated all currently known sub-species were found and the variation was labelled A. afarensis. Along with these bones was found footprints that clearly outlined the fully-upright stride of these creatures. However, recent discoveries made suggest that A. afarensis may have retained characteristics attributed to arboreal life, (tree dwelling).

The separation of these species of Australopithecus have resulted in many controversies the more known one is that regaridng the "Black Skull" found near Lake Turkana. Scientists have classifed this fossil has being part of the Australopithceus fmaily, a precursor to A. boisei. Others, however, propse that this skull is belonging to a new species-- Paranthropus, the name meaning "near man." The controversy has yet to be resolved.

The brain of Australopithecus, although still within close proximation of that of an ape's, was relatively larger than the average primate's. As well, neither gender had the projecting canine tetth used by apes in fighting. Australopithecus varied in size greatly, from less than 1.2m (4 feet), to the average size of a modern human. All of Australopithecus lived in open woodland and grassland rather than in forests as had the apes, their difference from the apes visible in their adaptation to their new habitat. Their front teeth were rather small while their rear grinding teeth were huge, indicating hard chewing. Scrathces on their dental enamel indicates that the diet of Australopithecus consisted mainly of hard, hewy seeds and berries. This species probably ate small animals as do chimpanzees, but most scientists consider it unlikely that Australopithecus was a systematic hunter.

The matter of tools is still being debated. Some believe that the broken bones and tusks of antelopes and other animals found at Australopithecus cave sites may have been used as tools or wepaons. Others believe it more likely that the broken animal bones were theleavings of leopards and hyenas that also frequented the caves. Some Australopithecus fossil sites yielded crude stone tools, these tools are more likely to be made from early true humans also found at these sites. However, the question remains, if Australopithecus was no more of a hunter or tool maker than a chimpanzee, why did it develop two-legged bipedalism?

Theories exist such as suggesting the Australopithecus babies had to be carried in the arms of their mothers, feet dragging, encouraging standing on two legs. Another believes that the freedom of hands as a way of defense was imperative with the lack of fangs and sharp teeth. Another sees the advantage of bipedalism as freeing hands to gather small, scattered vegetable foods on which Australopithecus usually fed. Whatever the cause, brain expansion can still be attributed to the bipedal phenomenon as well as the formation of "families" of one adult male and one or more females ad their young clustered in groups for protection.