The widely held notion that Neanderthals were dimwitted and that their inferior intelligence allowed them to be driven to extinction by the much brighter ancestors of modern humans is not supported by scientific evidence, according to a researcher at the University of Colorado Boulder.
Neanderthals thrived in a large swath of Europe and Asia between about , and 40, years ago. They disappeared after our ancestors, a group referred to as "anatomically modern humans," crossed into Europe from Africa. In the past, some researchers have tried to explain the demise of the Neanderthals by suggesting that the newcomers were superior to Neanderthals in key ways, including their ability to hunt, communicate, innovate and adapt to different environments.
But in an extensive review of recent Neanderthal research, CU-Boulder researcher Paola Villa and co-author Wil Roebroeks, an archaeologist at Leiden University in the Netherlands, make the case that the available evidence does not support the opinion that Neanderthals were less advanced than anatomically modern humans. Villa and Roebroeks scrutinized nearly a dozen common explanations for Neanderthal extinction that rely largely on the notion that the Neanderthals were inferior to anatomically modern humans.
These include the hypotheses that Neanderthals did not use complex, symbolic communication; that they were less efficient hunters who had inferior weapons; and that they had a narrow diet that put them at a competitive disadvantage to anatomically modern humans, who ate a broad range of things. The researchers found that none of the hypotheses were supported by the available research. For example, evidence from multiple archaeological sites in Europe suggests that Neanderthals hunted as a group, using the landscape to aid them.
Researchers have shown that Neanderthals likely herded hundreds of bison to their death by steering them into a sinkhole in southwestern France. At another site used by Neanderthals, this one in the Channel Islands, fossilized remains of 18 mammoths and five woolly rhinoceroses were discovered at the base of a deep ravine.
These findings imply that Neanderthals could plan ahead, communicate as a group and make efficient use of their surroundings, the authors said. Other archaeological evidence unearthed at Neanderthal sites provides reason to believe that Neanderthals did in fact have a diverse diet. Other predators, sitting atop the food chain, have few predators of their own, so overpopulation drives conflict over hunting grounds. This territoriality has deep roots in humans. Territorial conflicts are also intense in our closest relatives , chimpanzees.
Male chimps routinely gang up to attack and kill males from rival bands, a behaviour strikingly like human warfare. This implies that cooperative aggression evolved in a common ancestor of chimps and ourselves, at least seven million years ago. If so, Neanderthals will have inherited these same tendencies towards cooperative aggression. Even since the earliest discoveries of Neanderthal remains there have been theories that they were war-like Credit: Getty Images.
Warfare is an intrinsic part of being human. Historically, all peoples warred. Our oldest writings are filled with war stories.
Archaeology reveals ancient fortresses and battles , and sites of prehistoric massacres going back millennia. To war is human — and Neanderthals were very like us. Behaviourally, Neanderthals were astonishingly like us. They made fire , buried their dead , fashioned jewellery from seashells and animal teeth , made artwork and stone shrines.
If Neanderthals shared so many of our creative instincts, they probably shared many of our destructive instincts, too. Neanderthalensis were skilled big game hunters , using spears to take down deer, ibex, elk, bison, even rhinos and mammoths. It defies belief to think they would have hesitated to use these weapons if their families and lands were threatened.
Archaeology suggests such conflicts were commonplace. Prehistoric warfare leaves tell-tale signs. A club to the head is an efficient way to kill — clubs are fast, powerful, precise weapons — so prehistoric Homo sapiens frequently show trauma to the skull.
So too do Neanderthals. Measurement of our braincase and pelvic shape can reliably separate a modern human from a Neanderthal - their fossils exhibit a longer, lower skull and a wider pelvis. Even the three tiny bones of our middle ear, vital in hearing, can be readily distinguished from those of Neanderthals with careful measurement. In fact the shape differences in the ear bones are more marked, on average, than those that distinguish our closest living relatives - chimpanzees and gorillas - from each other.
Comparison of Neanderthal left and modern human right skulls, from a display in Cleveland Museum of Natural History. Pronounced differences in the braincase, ear bones and pelvis can still be recognised in fossils of Neanderthals and modern humans from , years ago. This suggests a separate evolutionary history going back much further - so far so good for differentiating H. Complications come when we consider a particular definition of species - one which Linnaeus did not develop, but which he probably would have appreciated.
The biological species concept states that species are reproductively isolated entities - that is, they breed within themselves but not with other species. Thus all living Homo sapiens have the potential to breed with each other, but could not successfully interbreed with gorillas or chimpanzees, our closest living relatives. Critics who disagree that H. This indicates that the two interbred with each other when they met outside Africa about 55, years ago.
In the face of this seemingly decisive evidence, why do I cling to my belief that Neanderthals and Homo sapiens are distinct species? Well, in my view the problem is not with ancient couplings between our ancestors and Neanderthals, but with the limitations of the biological species concept.
We now know from the same kind of genomic research that many other species of mammal interbreed with each other - for example different kinds of baboons genus Papio , wolves and wild dogs Canis , bears Ursus and large cats Panthera. A puma-leopard hybrid. You can see this specimen on display at the Museum at Tring. We now know that many mammal species can interbreed.
Thus the problem is not with Neanderthals and modern humans and all the other species that interbreed with each other, but with the biological species concept itself. It is only one of dozens of suggested species concepts, and one that is less useful in the genomic age, with its profuse demonstrations of inter-species mixing. The reality is that in most cases in mammals and birds, species diverge from each other gradually. It may take millions of years for full reproductive isolation to develop , something that clearly had not yet occurred for H.
In my view, if Neanderthals and Homo sapiens remained separate long enough to evolve such distinctive skull shapes, pelvises, and ear bones, they can be regarded as different species, interbreeding or not. Humans are great classifiers, and we do like to keep things orderly. But we should not be surprised when the natural world past and present does not match up to our neat and simple schemes.
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