At http://news.nationalgeographic.com/news/2010/01/100922-volcanoes-eruption-neanderthals/ and as reported elsewhere, a paper in the October issue of Current Anthropology suggests that volcanic eruptions in the Caucasus and Italy coincided with the demise of the Neanderthals. Pollen and ash was analysed in sediment layers dated from around 40,000 years ago. A sterile layer was found. The assumption of course is that sediments are laid down over a long period of time and in this instance that may not be the case. Volcanic eruptions can produce a lot of sedimentary material as is known from the fairly recent Mount St Helens eruption. It seems a sterile layer of ash and other material but lacking pollen and therefore signs of vegetative life was isolated, implying that for a period plants and trees did not grow. This in turn, it was decided, coincided with the Campania Ignimbrite eruption in the Naples region of Italy. Basically, they are saying loss of plants led to a decline in plant eating animals which in turn affected the Neanderthals – who are assumed to have wholly existed on red meat from large herbivores. Unable to adapt they became extinct.
According to the paper a whole raft of volcanoes erupted at the same time – which sounds awfully like a catastrophe. However, they do not seem to have located the triggering agency. Something must have caused those volcanoes to erupt simultaneously – but see Firestone, West and Warwick-Smith, The Cycle of Cosmic Catastrophes for further evidence of something peculiar going on around 40,000 years ago.
Note … this date is normally revised to 35,000 years ago, or even a little more recently. The problem is caused by the fact this is the upper limit of C14 methodology and when combined with a C14 plateau event (an injection) it tends to produce a divergence in dates obtained by laboratories – and there are no trees to calibrate the dates as early as that.
The authors, we may note, only look at evidence in Europe – they do not seek collaboratory data from outside that one particular region. They don’t need to of course as they are only concerned with the part of the world inhabited by Neanderthals. Is there evidence of volcanism at the same point in time from Africa, Asia or the Americas? It just so happens that some time between 40 and 30,000 years ago large numbers of mammoths and other large mammals were killed in a huge die-off in the northern hemisphere while in Australia we had what is known as the Megafauna extinctions. These are usually blamed on Aborigines as there is evidence of wildfires across the landscape and Aborigines are known to have used fires as a hunting strategy – in imitation of nature.