Neanderthals probably froze to death in the last ice age because rapid climate change caught them by surprise without the tools needed to make warm clothes, finds new research. Ian Gilligan, a postgraduate researcher from the Australian National University argues his case in the current issue of the journal World Archaeology. By the time some Neanderthals developed sewing tools it was too little too late, said Gilligan.
     Neanderthals began to die out just before the last glacial maximum, 35,000 to 30,000 years ago and were replaced by modern humans. Previous studies have argued that one of the key reasons for this is that modern humans had better hunting tools, providing them with the extra food they needed to survive the cold. But Gilligan disagrees that the development of hunting tools was so important to modern humans' survival over the Neanderthals. For a start, he argues, Neanderthals were already successful hunters, surviving in Europe and Eurasia for over 100,000 years. Most of the tools supposed to have given modern humans the edge over Neanderthals were actually more useful for making warm clothes.
     The important tools developed by modern humans included stone blades, bone points and eventually needles, which could cut and pierce hides to sew them together into multi-layered clothes including underwear, said Gilligan. "They're not related to hunting, they're related to clothing," he said. "These tools are related to tailored, fitted clothing, what I call complex clothing." Modern humans were more vulnerable to the cold than Neanderthals and developed these tools as far back as 90,000 years ago to cope with cooler parts of Africa, before the peak of the ice age.
     But Neanderthals were physically more resistant to the cold, said Gilligan. Because of this they were quite happy before the ice age to get around in similar temperatures wearing little less than single-layered loosely-draped animal hides. This gave Neanderthals no pressing need to develop complex clothing. But when the peak of the ice age came, it was a shock.
     Over brief periods, the average temperature would plunge by more than 10 degrees Celsius (50 degrees Fahrenheit) and then warm again before plunging once again into ultra-cold territory, says Gilligan. Neanderthals were unable to adapt their clothing in response to such rapid climate change. While there is evidence that some Neanderthals in France started to develop sewing tools, this would not have been enough to save the species.

Sources: ABC Science Online, Discovery Channel (3 January 2008)