Neanderthals 'died out later than previously thought'

Since the 1990s, scholars have believed that around 35,000 years ago the last of the Neanderthals sought refuge in southern Iberia, in an area known as Spain today. However, new dating evidence on fossilised bones from sites in the region suggests that the fossils could be 15,000 years older than previously thought. The findings, which have implications for whether Neanderthals and modern humans co-existed, are published in the early edition of Proceedings of the National Academy of Sciences . The work was undertaken by Rachel Wood and Thomas Higham at the Oxford Radiocarbon Accelerator Unit at the University of Oxford, as well as a team of Spanish archaeologists. The researchers used an improved dating method called 'ultrafiltration' that removes modern carbon that can contaminate the ancient collagen in bones, thereby giving inaccurate younger dates. The team tested 215 bones from 11 sites in southern Iberia where previous radiocarbon dating work had supported the late survival of Neanderthals. Radiocarbon dating is particularly sensitive to modern contaminants, which is why the ultrafiltration process was so important.