Homo georgicus is the name proposed to describe fossil human remains that have been found at the medieval town of Dmanisi, Georgia from 1991. The site has been of interest to archaeologists for many years and bones of extinct mammals had previously been recovered from the site. Mode I stone tools, similar to the Oldowan tradition of East Africa, and comprising flakes and flaked pebbles were discovered in 1984. The human remains include four partial human skulls and two lower jaws.
A basalt layer below the fossils has been dated to between 1.95-1.77 million years old by magnetic polarity considerations, which are normal. The material occurring with the fossils shows reversed polarity, dating it from 1.77 million to 790,000 years. The mammal bones do suggest the earlier date based on when certain species overlapped in time.
The skull known as D2700 has an extremely small braincase volume of 600cc, similar to that of Homo habilis and it has been suggested that it has a closer relationship to this species than it does to African Homo ergaster or Asian Homo erectus. If so, it would imply that humans of the habilis rather than the erectus grade were the first to leave Africa. However a recent description of a metatarsal shows a close fit with the derived Homo ergaster body plan rather than that of Homo habilis, which retained many australopithecine features.
References:
Cameron D & Groves C (2004): Bones, Stones and Molecules: “Out of Africa” and Human Origins, Elsevier Academic Press.
Scarre C (2005) (Ed): “The human past”, Thames & Hudson.
Abesalom Vekua, David Lordkipanidze, G. Philip Rightmire, Jordi Agusti, Reid Ferring, Givi Maisuradze, Alexander Mouskhelishvili, Medea Nioradze,
Marcia Ponce de Leon, Martha Tappen, Merab Tvalchrelidze, Christoph Zollikofer (2002): A New Skull of Early Homo from Dmanisi, Georgia, Science 297, 85 (2002).
© Christopher Seddon 2008
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