Homo habilis

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"""Homo habilis""" is an enigmatic early hominin species found dominantly in East African fossil deposits dated to approximately 1.8 to 2 million years ago.

With a larger brain than the australopithecines (around 600 – 710cc), "H. habilis", meaning “handy man”, was the first species of extinct hominin placed in the genus "Homo"[1][2].

History of Discovery

The first specimen was found by Mary Leakey at Olduvai Gorge in 1960[2]With its rounder head, reduced prognathism, more human-like teeth and less pronounced brow ridges, it was interpreted as being considerably more “human-like” in appearance and thus possibly ancestral to "H. erectus"[3] Little is known about this species, in large part because there is little agreement as to exactly which fossils can be ascribed to it in both East and South Africa[4].

Description

"H. habilis" is complex to describe and there is considerable debate concerning which specimens are definitively placed into this speciesCite error: Closing </ref> missing for <ref> tag.

Taxonomic status

Some researchers have recently suggested that fossils attributed to "H. habilis" would be better placed into the genus "Australopithecus" based in part upon certain morphological characters, the limited number of characters that separate it from earlier australopithecines and the perceived presence of other more derived members of the genus "Homo" present during the same temporal period[5]. Whether habilis remains in the genus Homo or in the genus Australopithecus has not been completely resolved[5].

Language in "H. habilis"

It has been suggested that "H. habilis" had the capacity for complex language, but confirmation of this is difficult as it is based largely on poorly preserved endocasts (cast of the brain made by making an impression of the interior of the skull).

Occurrences

Fossil attributed to "H. habilis" have been found at Olduvai Gorge in Tanzania, as well as Koobi Fora in Kenya. "H. habilis " has been described from Sterkfontein in South Africa, though this identification has been questioned.

Temporal range

Its estimated time range in Africa is from just over 2 million years until about 1.5 million years when it apparently became extinct.

Tool making and use=

"H. habilis" has long been associated with the crude Oldowan tool industry[1]. It is possible that the earliest stone tools in Africa at 2.5 million years of age in Ethiopia were produced by Homo habilis, but again confirmation is difficult and there are several other early Homo species and even australopithecines that are temporally associated with these early tools.

Important "Homo habilis fossils"

  • OH-7 – the holotype of "H. habilis".
  • OH-8 a nearly complete foot that has been bitten by a crocodile.
  • OH-24 – nicknamed “Twiggy”
  • Oh-62 – a partial skeleton from Olduvai Gorge, Tanzania.
  • Stw 53 – a possible H. habilis skull from Sterkfontein, South Africa.

Homo habilis sites

Odluvai Gorge, Tanzania Koobi for a, Kenya Sterkfontein, South Africa (possible)

References

  1. 1.0 1.1 L.S.B. Leakey, Tobias, P.V. and Napier, J. (1964). A new species of genus "Homo" from Olduvai Gorge. Nature. 
  2. 2.0 2.1 P.V. Tobias (1991). Olduvai Gorge Volume 4. The Skulls, Endocasts, and Teeth of "Homo habilis". New York: Cambridge University Press. 
  3. C. David Kreger (2006). "Homo habilis". Archeology.info.
  4. B. Wood (1993). Early "Homo": How many species?" In Species, Species Concepts, and Primate Evolution, ed. by W.H. Kimbel, and L.B. Martin. Plenum Press. 
  5. 5.0 5.1 M. Wolpoff (1999). Paleoanthropology. J. Hum Evol..