Study sheds new light on Neanderthals' demise
Scientists in Ireland and Russia have discovered that Neanderthals probably died earlier than what is commonly believed. Presented in the journal PNAS Online Early Edition, the study puts a new spin on the theory that ties between Neanderthals and modern humans existed for thousands of years. The finding suggests that interactions between them were neither unrestricted nor long-lasting; it is likely that Neanderthals and modern humans co-existed for just a few hundred years. It could even be possible that Neanderthals in some areas became extinct before anatomically modern humans emigrated from Africa. Experts from University College Cork in Ireland and the University of Oxford in the UK, in cooperation with researchers at the Laboratory of Prehistory at St Petersburg in Russia, carried out their study on Mezmaiskaya Cave, which is located in the northwestern foothills of the Caucasus Mountains in Russia. In this area, the team found a fossil of a late Neanderthal infant from the Late Middle Palaeolithic layer and a series of associated animal bones. They say the fossil was 39,700 years old, suggesting that Neanderthals did not survive at the cave site beyond this time. In a nutshell, the data questions what researchers have long believed about late Neanderthals and their survival. Late Neanderthals did not survive until 30,000 years ago in the northern Caucasus; so it is very unlikely that Neanderthals and modern humans co-existed for any significant period of time. Armed with this new information, the researchers believe one of two developments: that Neanderthals became extinct when modern humans arrived; or that other factors, including climate change or shrinking resources, led to their demise before the arrival of modern humans. The researchers say data must be revised, amended and improved if accurate chronologies are to emerge. Doing this will result in delivering correct assessments of the possible relationship between Neanderthal extinctions, dispersals of early modern humans and climatic events. The team points out that previous dating processes appear to have 'systemically underestimated' the actual age of Late Middle Palaeolithic and Early Upper Palaeolithic deposits, fossils and artefacts by around several thousand years. 'It now seems much clearer that Neanderthals and anatomically modern humans did not co-exist in the Caucasus, and it is possible that this scenario is also true for most regions of Europe,' says Dr Ron Pinhasi of University College Cork, the lead author of the study. 'Many of the previous dates for late Neanderthal occupation of sites across Europe are problematic. This is simply an outcome of the fact that the association between the dated material and late Neanderthals is not always clear because we cannot always be certain whether archaeological stone tool assemblages, such as the Mousterian, that has been attributed in the case of Europe to Neanderthals, was not in some cases actually produced by modern humans. We have to directly date Neanderthal and anatomically modern human fossils to resolve this.' For his part, Oxford's Dr Tom Higham, a co-author of the paper, says: 'The latest dating techniques mean we can purify the collagen extracted from tiny fragments of fossil very effectively without contaminating it. Previously, research teams have provided younger dates which we now know are not robust, possibly because the fossil has become contaminated with more modern particles. This latest dating evidence sheds further light on the extinction dates for Neanderthals in this key region, which is seen by many as a crossroads for the movement of modern humans into the wider Russian plains. The extinction of Neanderthals here is, therefore, an indicator we think, of when that first probably happened.'For more information, please visit: University College Cork: http://www.ucc.ie/en/ PNAS Online Early Edition: http://www.pnas.org/content/early/recent
Countries
Ireland, Russia