Homo habilis

Homo habilis first appeared around 2.5 million years ago. Fossils of H. habilis were first discovered in Olduvai Gorge in Tanzania and named by Louis Leakey, Phillip Tobias, and John Napier. Fossils of this species were also found at Lake Turkana, Kenya, Omo Basin, Ethiopia, and Sterkfontein Cave, South Africa. Excavations at Olduvai Gorge also indicate that H. habilis lived at the same time and in the same place as P. boisei.

Tools have been found at the Olduvai site, at the same level as P. boisei and H. habilis. These tools are called Oldowan tools. They are simple pebble tools made from water worn cobbles about 3"- 4" in diameter. The Oldowan tools are made by knocking off a few flakes from one or two faces of the stone, thus creating a sharp edge. The tools were initially found at the same level as P. boisei and H. habilis, but "zinj" (P. bosiei) was thought to be to primitive to use the tools. H. habilis with a larger brain size was a more likely candidate to be using the tools. The tools were most likely used by hominids to make a scavenging lifestyle more efficient. Oldowan tools allowed hominid's to more easily and quickly remove meat and bones from a carcass. This made the addition of meat to their diet a more efficient practice. Also, the genus Homo is the only genus of hominid that evidence is found of tool use.

With a relatively larger brain, 680cc on average and up to about 800cc, than the Australopithecines, Homo habilis is the first definite human ancestor. Homo habilis is considered to be the first member of the genus homo because of two main reasons. First, their larger brain size, and second, the presence of tools indicates that the large brains were capable of more complex thought processes not seen in the Australopithecines. H. habilis marked a trend in hominid evolution toward larger brains and more intelligence. In addition to this larger brain size, H. habilis remains also have reduced molars and premolars and a clearly bi-pedal foot structure.

Approximately 1.6 million years ago, Homo habilis was replaced by Homo erectus.

References:

Day, M.H. The Fossil History of Man. Oxford University Press. Burlington, NC. 1977.

Ember, Carol R. Anthropology A Brief Introduction 4th Edition. Prentice Hall Inc. Upper Saddle River, NJ. 2000.

Larsen, Clark. Human Origins 2nd Edition. Waveland Press Inc. Prospect Heights, IL. 1991.

Park, Michael A. Biological Anthropology 4th Edition. McGraw-Hill. New York, New York. 2005.

Edited By:

Jared Langseth, 2005