Australopithecus is a genus of extinct hominids which lived in Africa from about 4.2 million until about 1 million years ago. It is still uncertain whether Australopithecines were a direct ancestor of humans or whether the genus Homo (to which humans belong) branched off from a still-earlier genus of hominid. Australopithecines were more chimp than human, standing 1-1.2m (3.3-3.9 ft) tall, with a small brain measuring between 370 and 515 cubic centimeters (146-203 inches). This is only about 35% the size of the modern human brain. Australopithecines were mostly bipedal but not very intelligent, possessing only a very primitive tool industry.
Australopithecines were thought to have been adapted for both tree-climbing and bipedal or semi-bipedal locomotion. Australopithecines species include A. afarensis, A. africanus, A. anamensis and A. garhi. P. boisei, P. robustus, and P. aethiopicus used to be considered a part of the genus Australopithecines, until they were reclassified in the genus Paranthropus.
It was not until 1994 that the first complete Australopithecine skull was discovered. In 1974, the "Lucy" specimen of A. africanus was discovered in the Afar Depression of Ethiopia, a 40% complete fossil that was one of the first to become a household name. The discovery of this fossil and its surrounding story has become a part of many middle school and high school curricula, being referenced as a key piece of evidence that humans evolved from chimps.
Australopithecines are often referenced as the first hominid genus to develop bipedalism. This allowed the animal to stand upright and gain a better view of its surroundings, allowing it to spot predators over high grass. This was an important stepping stone in moving the hominid line from jungle life to savanna life. Australopithecines primarily lived in the Pliocene epoch, which extends from 5.3 million to 1.8 million years ago.
For many decades, Creationists have called Australopithecines just another type of chimp, though most of the educated world has long rejected this view. Australopithecines possess anatomical features characteristically associated with both chimps and humans, and are one of the most heavily-studied fossil sets in hominid paleontology. One of the features most frequently referenced as being human-like is the shape of Australopithecines teeth.