Wednesday, 9 September 2009

Out of Georgia

There was an interesting talk at the British Science Festival in Guildford yesterday about hominid finds in Dmanisi, Georgia. The story itself is not new, with the first discoveries being made back in early 1990s, but the talk discussed the current thinking on the finds. You can read a little about it here, but the article is more than a little hyperbolic in its claims that the finds demolish the Out of Africa theory.

The skeletons and skulls date to around 1.8 million years old and are a more primitive species than Homo erectus, the folks responsible for what had previously been considered the first road trip out of Africa, around 1 million years ago. H. sapiens, us lot, didn't get round to heading North until relatively recently, maybe 100,000 years ago. Imagine the packing that went on. 'Look, I'm sure you're not going to need all those loin cloths. Just bring the extra hairy ones; it's probably going to be freezing.'

While still not certain, the Dmanisi finds resemble a more developed H. habilis or possibly closer to H. ergaster. It had been thought that erectus had been the most primitive hominid to make the trip into Eurasia. While the Out of Africa theory had regarded two major excursions from the continent as being the most significant, it had never ruled out any number of others at different times. It seems that these early Georgians had made the journey some considerable time before the more evolved erectus left for pastures new, but that does nothing to undermine the theory's main points, as the species was clearly a bit of an evolutionary dead end.

The article linked to above suggests that at some point the Georgian hominids may have made the return journey to Africa and continued to feed into the evolutionary melting pot. I see no need for this to have happened at all. Seems much more likely that not everyone went North in the first place and that probably the majority of the species stayed at home, where it was warm and they knew they could get tasty antelope.

Anyway - it's a topic I find fascinating. One thing is certain - as more finds are made, more evidence is revealed and we will be able to add to the story of human evolution and expansion from Africa.

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