They vanished from the Earth around 40,000 years ago after surviving for hundreds of thousands of years through much of the last ice age. Now researchers believe they may have uncovered a possible explanation of what may have contributed to Neanderthals eventual demise - they were not very adept at controlling fire. A team of archaeologists at Boston University and the University of Bath believe this would have meant they lost out when modern humans arrived from Africa. Neanderthals, like the reconstruction above on display at the Natural History Museum in London, may have finally died out as they were unable to get as much energy from their food as modern humans who used fire . They used computer model the amount of energy Neanderthals would have been able to get from their food without cooking it compared to humans that were. They found that without fire, a group of Neanderthals would have had less energy - the equivalent 12 reindeer a year - than if they did. They are often depicted as dim-witted evolutionary losers, but Neanderthals were not driven to extinction by their lack of brains.. Instead, it is more likely that they disappeared 40,000 years ago because of interbreeding and assimilation with our early modern human ancestors, scientists believe. An analysis of archaeological evidence dating back 200,000 years strips away some of the myths surrounding Neanderthals and reveals they were more advanced and sophisticated than has widely been thought. Many researchers believe the differences between the two human species are not enough on their own to account for the demise of the Neanderthals. Neanderthals have been found to make stone tools and even made jewellery. Eight talons taken from a white-tailed eagle found at Neanderthal site in Krapina in Croatia were used to create a necklace or bracelet 130,000 years ago. Modern humans who regularly cooked their food could have then channeled this extra energy into growing their population and searching longer for food during lean periods. Anna Goldfield, an archaeologist at Boston University who led the research, said: 'Cooking makes meat more easily digestible, and that means that the calories that would've been used to digest raw meat can go to other uses. 'I determined, importantly, that a diet of cooked meat meant that either foraging groups could travel a bit farther in their range of gathering, or since they were getting more out of a set of resources, they could stay longer in the same landscape.' Living from about 300,000 years ago to 40,000 years ago, they were known to make stone tools and were accomplished hunters. They spread through out Europe and much of Asia, and there is some evidence that they made jewellery and art. Some researchers believe that they were also highly intelligent - possibly even as intelligent as modern humans, Homo sapiens. There are a number of theories for what caused Neanderthals to disappear - but most seem to agree it was the arrival of modern humans in Europe and Asia that played a role. Some archaeologists believe they were unable to compete with modern humans, while others believe humans actively killed them. Neanderthals vanished relatively quickly once modern humans arrived in the areas where they were living . However, DNA evidence also suggests that Neanderthals and modern humans also interbred. Neanderthals use of fire is still a highly controversial issue, but if they had not used it to cook food as much as modern humans it would have put them at a definite disadvantage. Miss Goldfield said: 'There is certainly plenty of evidence that Neanderthals used fire in Europe as well as in the Levant, Africa, and elsewhere. 'I was absolutely not suggesting that Neanderthals had no use or control of fire. What we don't know is how intensively the populations used fire. 'What is an intriguing problem is the seeming lack of consistent fire use in the Quina Mousterian, a glacial phase of the Middle Paleolithic. 'We see a bit of burned bone at some sites, but really no evidence for lots of fire use. It may be that we haven't found it yet, or it may be that Neanderthals were using other survival strategies. 'Neanderthals probably weren't all that different from humans, but they may have adopted different strategies for dealing with their environment.' Miss Goldfield, who conducted her research with Ross Booton, a mathematical biologist at the University of Sheffield, suggests that with their bigger bodies, Neanderthals would have needed more food than modern humans. Recent research is suggesting that Neanderthals were sophisticated and not very different from modern humans, increasing the mystery behind why they died out and Homo sapiens managed to survive . She said: 'My real aim was to specifically look at the impact of cooking on metabolism, and whether regular cooking of food might have been an advantage for Neanderthals. 'Neanderthals were a bit more muscular and robust than early humans. Neanderthal metabolic costs for a day's activity would have been a bit higher.' Using their computer models they were able to simulate how the populations of Neanderthals would change depending on their use of fire. They found that if modern humans used fire more often than Neanderthals, then their populations would grow. Both groups hunted and ate reindeer, among other large prey, that were prevalanet across much of Europe at the time. But as modern human populations grew, it would also reduce the number of reindeer available for Neanderthals. Over time this could have increased Neanderthals vulnerability to extinction. Miss Goldfield presented her findings at the Annual Meeting of the Society for American Archaeology in San Francisco. She said: 'Initial tests indimcate that cooking lean meat increases its caloric value sufficiently to offset up to 3.7 days’ worth of locomotion, or 12 kills per year, thus extending the carrying capacity of a landscape patch, particularly during periods of resource scarcity.' She told LiveScience: 'Fire use would have provided a significant advantage for the human population and may indeed have been an important factor in the overall collapse or absorption of the Neanderthal population.'
Researchers used computer models to study how Neanderthal populations would have fared if they did not use fire to cook and modern humans did . They found cooking would have increased the number of calories available . Evidence for Neanderthals using fire is patchy and not all may have done it .