There were just too many humans for Neanderthals to survive

The extinction of the Neanderthals remains a matter of intense debate. Were we smarter than them? More warlike? Or perhaps we simply sexed them into extinction? The real answer might have more to do with our quantity than our qualities.

For about 300,000 years, Europe was pretty much the undisputed domain of the Neanderthals. About 60,000 years ago, modern humans entered the continent, and by 40,000 years ago, the Neanderthals were gone forever. It's difficult to figure out just what caused this extinction - and it's almost certain that multiple factors were in play - but Cambridge researchers now think they've hit upon the primary reason why Neanderthals died out: there simply weren't enough of them to compete.

According to complex statistical analysis of the so-called "Perigord" region of southwestern France - which has the highest concentration of early human and Neanderthal sites in all of Europe - the earliest human immigrants to the continent instantly outnumbered the Neanderthals by a factor of 10 to 1. The basis for this conclusion is the massive uptick in the number of human sites, the fact that these sites were more densely populated than their Neanderthal counterparts - which we can tell from the far more pronounced presence of animal bones and stone tools - and the fact that these human sites extended over larger areas, indicating the formation of larger social groups.

With a built-in population advantage like that, human "victory" over Neanderthals could never have been in doubt. (I suppose the only things that could have stopped humans were exotic diseases - and humans solved that problem by breeding with Neanderthals.) Where Neanderthals had once had unchallenged domain over their hunting grounds and the resources needed to survive the cruel winters, they now could only stake an eleventh of a claim, and they were going up against interlopers who likely had superior technology and possibly had superior intellect, though both of those assertions remain controversial.

Professor Paul Mellars explains:

"In any event, it was clearly this range of new technological and behavioural innovations which allowed the modern human populations to invade and survive in much larger population numbers than those of the preceding Neanderthals across the whole of the European continent. Faced with this kind of competition, the Neanderthals seem to have retreated initially into more marginal and less attractive regions of the continent and eventually — within a space of at most a few thousand years — for their populations to have declined to extinction — perhaps accelerated further by sudden climatic deterioration across the continent around 40,000 years ago."

We still have some work to do in establishing the finer causes of why humans supplanted Neanderthals in Europe, not to mention figuring out the long-term legacy of interaction between Neanderthals and humans. But this research probably does provide the major reason. After all, if you have two even vaguely evenly matched species and you give one of them a 10-to-1 numbers advantage, it's not hard to guess which of the two species will come out on top.

Via Science. Image via.