Stone Age people under the water

18 Feb 2012

At www.bbc.co.uk/news/uk-english-hampshire-17046338/ ... there is a video of the stone age boatyard found on the bottom of the Solent - since flooded by rising sea levels.

There are also lots of pictures, and lots of text on the Blombos Cave excavations in South Africa - see www.nature.com/news/human-evolution-cultural-roots-1.10025  Chris Henshilwood has found occurpation layers in the cave followed by long gaps where no human activity is discernible. For example, the Still Bay culture appeared around 78,000 years ago but by 71,000 years ago it had disappeared. A new culture group occupied the cave after 7000 years - but where did the first one go? Henshilwood thinks climate was to blame, an onset of Ice Age conditions that caused sea levels to drop - dramatically. He suggests people may simply have spread out over the continental shelf (now under water) and they had not disappeared, as such, but had moved - but why did they not return later?

In other parts of the world there does seem to have been a bit of a population drop around 70,000+ years ago so the evidence of the disappearing culture is not out of sync. Did sea levels drop at the same time? Henshilwood hopes to find what happened and some work on this aspect has been done by another excavator in the Cape Province, Curtis Marsen, at Pinnacle Point - which goes back to 164,000 years ago. He has produced an assessment of historical sea level change near his site but there appears to be anomalies when evidence in other parts of Africa is compared with it. It is hoped that by using up to date sophisticated technology, and presumably computer models, some kind of rational graph on sea levels can be produced - on the assumption that it is the Ice Age that is responsible for the sea level changes.