The bones of a Neanderthal man's skeleton, found during several excavations.
Credit: AFP
WASHINGTON: A swell of modern humans outnumbered Neanderthals in Europe by nearly 10 to one, forcing their extinction 40,000 years ago, suggests a new study.
Scientists have long debated what caused the Neanderthals to die off rather suddenly, making way for the thriving population of more advanced Homo sapiens who likely moved in from Africa.
The latest theory, published in Science, is based on a statistical analysis of artefacts and evidence from the Perigord region of southern France, which contains the largest concentration of Neanderthal and early modern human sites in Europe.
Researchers at the University of Cambridge found more sites where modern humans settled, larger settlement areas, greater densities of tools and bigger amounts of animal and food remains, suggesting that Neanderthals were crowded out.
More highly developed brains?
Whether the incoming modern human groups possessed more highly developed brains and associated mental capacities than the Neanderthals remains at present a matter of intense debate.
But the sudden appearance of a wide range of complex and sophisticated art forms such as cave paintings, the large-scale production of elaborate decorative items, such as perforated stone and ivory beads, and clearly 'symbolic' systems of markings on bone and ivory tools, strongly point to more elaborate systems of social communications among the modern groups.
These were probably accompanied by more advanced and complex forms of language, and were all entirely lacking among the preceding Neanderthals.
Faced with such a dramatic increase in the incoming modern human population, the capacity of the local Neanderthal groups to compete for the same range of living sites, the same range of animal food supplies (principally reindeer, horse, bison and red deer), and the same scarce fuel supplies to tide the groups over the extremely harsh glacial winters, would have been massively undermined.
Neanderthals were out-competed
Plus, almost inevitably, repeated conflicts or confrontations between the two populations would arise for occupation of the most attractive locations and richest food supplies, in which the increased numbers and more highly coordinated activities of the modern human groups would ensure their success over the Neanderthal groups.
"It was clearly this range of new technological and behavioral 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," said lead author Paul Mellars of Cambridge University. "Faced with this kind of competition, the Neanderthals seem to have retreated initially into more marginal and less attractive regions of the continent."
The final deathblow
If, as the latest genetic evidence strongly suggests, the African Homo sapiens and European Neanderthal populations had been evolving separately for at least half a million years, then the emergence of some significant contrasts in the mental capacities of the two lineages would not be a particularly surprising development, in evolutionary terms.
All of these new and more complex behavioural patterns can be shown to have developed first among the ancestral African Homo sapiens populations, at least 20,0000 to 30,000 years before their dispersal from Africa, and progressive colonisation (and replacement of earlier populations) across all regions of Europe and Asia from around 60,000 years onwards.
Mellars suggested a final deathblow may have been delivered by a harsh cold snap, a theory that has been debated in the scientific community for many years. The Neanderthals' extinction may have been "accelerated further by sudden climatic deterioration across the continent around 40,000 years ago," he said.
