Australopithecus is one of several species of hominins who may or may not be Homo sapiens direct ancestor. Fossils of Australopithecus have been found in Africa dating to the period between 4.2 and 1.4 million years ago. They discovered how to use tools approximately 2 million years ago, marking the beginning of the Lower Paleolithic period.
Australopithecus used bipedal locomotion (walked upright on two legs), had a long forearm and lumbar column relative to African or Asian apes, stood between 1.2 and 1.5 meters, and had a body mass of 30-35 kilograms and a brain size between 350 and 600 cubic centimeters.
In general, scientists recognize seven species of the genus Australopithecus (although certainly there is debate). A. sebida, reported in 2011, may not be Australopithecus, and reports suggest that the species definition may need revising.
- Australopithecus afarensis, 3.6-2.9 million years ago (mya). Laetoli (Tanzania), Koobi Fora and West Turkana (Kenya), Omo and Selam aka Dikika (Ethiopia), Middle Awash and Hadar regions in Ethiopia, Sterkfontein, South Africa
- A. aethiopicus, 2.7-2.3 mya. West Turkana in Kenya, Omo Shungura in Ethiopia.
- A. africanus, 3-2 mya. Makapansgat, Sterkfontein, Taung in South Africa.
- A. anamensis, 4.17-3.9 mya. Kanapoi and Allia Bay in Kenya, Fejej and Galili in Ethiopia.
- A. bahrelghazali, 3.5-3.0 mya. Koro-Toro in Chad.
- A. boisei (sometimes designated Paranthropus boisei), 2.3-1.4 million years ago. Chiwondo in Malawi, Olduvai Gorge and Peninj in Tanzania, Koobi Fora and West Turkana in Kenya, Omo Shungura and Konso-Gardula in Ethiopia.
- A. garhi 2.5 mya. Bouri and Omo Shungura in Ethiopia, Baringo-Chemeron in Kenya.
- A. robustus, 1.7 mya. Kromdraai, Swartkrans, Drimolen and Gondolin, South Africa.
- A. sebida, 1.977 mya. Malapa cave, South Africa.
This definition is part of the About.com Guide to the Lower Paleolithic.
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