摘要：英国剑桥大学科学家２８日提出新观点认为，现代人的祖先在数量上占压倒优势，可能是尼安德特人最终灭绝的原因之一。
尼安德特人是早期曾占据欧洲大陆和亚洲部分地区的一种古人类，大约在３万年前消失，被智人也就是现代人所取代，科学界对其灭绝原因一直未有定论。
剑桥大学考古系教授保罗·迈拉尔斯等人，对法国南部拥有大量尼安德特人以及早期智人定居点遗址的地区进行了考古分析。他们观察了从５．５万年至３．５万年前的３个界限清楚的考古时期，其中包括了尼安德特人到智人的过渡期。
分析发现，在过渡期，早期智人数量约为尼安德特人的９倍到１０倍，前者定居点面积、工具密度以及动物、食物遗迹数量也大于后者；此外，早期智人遗留的石器工具、首饰以及艺术品也表明，他们拥有更复杂的社会网络。
研究人员认为，早期智人的压倒性数量优势迫使尼安德特人迁往更难发现食物和庇护所的地方，最终，伴随着４万年前欧洲大陆的气候恶化，尼安德特人逐渐灭绝。
这项研究７月２９日发表在美国新一期《科学》杂志上。
现代人的祖先在数量上占压倒优势，可能是尼安德特人最终灭绝的原因之一
生物探索推荐英文论文摘要：
Science 29 July 2011:
Vol. 333 no. 6042 pp. 623-627
DOI: 10.1126/science.1206930
Tenfold Population Increase in Western Europe at the Neandertal–to–Modern Human Transition
ABSTRACT
European Neandertals were replaced by modern human populations from Africa ~40,000 years ago. Archaeological evidence from the best-documented region of Europe shows that during this replacement human populations increased by one order of magnitude, suggesting that numerical supremacy alone may have been a critical factor in facilitating this replacement.
生物探索推荐英文原文报道：
Neanderthals' demise caused by modern human invasion
Homo sapiens from Africa swarming into Europe outnumbered neanderthals by 10 to one 40,000 years ago, claim scientists
Neanderthals in Europe were overrun by a huge invasion of African homo sapiens 40,000 years ago, which may explain their demise, claim Cambridge scientists.
Neanderthals died out in Western Europe after a surge of modern humans arrived from Africa and made them a minority in their own land, researchers claim.
The swarm of homo sapiens onto the continent more than 40,000 years ago left the neanderthals, who had thrived in the frigid conditions for 300 millennia, outnumbered by a massive 10 to one.
The invasion of so many modern humans overturned the neanderthals' domination of the land and forced them into fierce competition for food, fuel and other crucial resources.
The scenario, described by Paul Mellars, emeritus professor of prehistory and human evolution at Cambridge University, and his colleague, Jennifer French, is the latest attempt by scientists to explain the mystery of the neanderthals' demise.
Modern humans, along with environmental factors, have long been suspects in the sudden extinction of our thick-browed relatives, but the nature of their decline is still under debate.
Mellars and French analysed archaeological evidence in Périgord, a former province of southwestern France, which is renowned for its neanderthal and early human sites. They found that the population of homo sapiens that arrived in the region was at least ten times larger than that of the neanderthals already settled there.
In particular, the area saw a sharp rise in the number and size of early human sites and the detritus of life they left behind, such as stone tools and the remains of animal carcasses, according to a report in Science.
The researchers believe the sheer pressure of being outnumbered was exacerbated by the social and technological advantages that modern humans displayed, from long-range hunting spears to stronger cooperation and communication. The arrival of modern humans coincided with the appearence of elaborate cave paintings, decorative stones and beads, and imported shells, suggesting homo sapiens had a more complex society than the neanderthals.
"It was clearly this range of new technological and behavioural innovations which allowed the modern human populations to invade and survive in much large population numbers than those of the preceding neanderthals across the whole of the European continent," said Mellars.
"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 hundred 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."
