Did global warming kill off the woolly mammoth? Scientists say it may have been climate change that wiped out the beasts
By Fiona Macrae
Last updated at 11:23 AM on 18th August 2010
Human have always taken the blame for wiping out the woolly mammoth.
But although man hunted the beasts for their skin and meat, scientists believe it may actually be climate change that killed the mammoth off.
Some 21,000 years ago, after the last Ice Age, warmer temperatures led to a loss of grassland over much of the Earth’s surface.
Victim of global warming? Scientists believe it may actually have been climate change that killed the mammoth offAs the prairies and steppes dwindled, spreading forests took their place. These changes made survival impossible for the big, grazing herbivores and the predators that fed on them, according to a Durham University study, the most comprehensive of his kind.
Researcher Professor Brian Huntley said: ‘Woolly mammoths retreated to northern Siberia 14,000 years ago, whereas they had roamed and munched their way across many parts of Europe, including the UK, for most of the previous 100,000 years.
'It would have been difficult for man to wipe them out because our species was not so widespread then and did not have the technology.
‘We know from mammoth fossils that they were hunted by humans. But they would not have been an easy kill because of their size.’
His research on the climate firmly points the finger at rising temperatures.
The woolly rhino, cave lion, giant deer and cave bear also failed to survive the new conditions.
Although some small pockets may have clung on, their fate had effectively been sealed.
‘Mega-mammals found it increasingly difficult to find food,’ said Dr Huntley. ‘We believe the loss of food supplies from productive grasslands was the major
contributing factor to extinction.’
The Durham experts, who worked with researchers from London’s Natural History
Museum, report their findings in the journal Quaternary Science Reviews.
And they say we should learn the lessons of the past.
‘This is a model for what may happen as a result of rapid climate change over the next century,’ said Dr Huntley.
Big species today, such as the elephant, are likely to be among the first affected by climate change, he added.
http://www.dailymail.co.uk/sciencetech/article-1303981/Did-global-warming-kill-woolly-mammoth.html
科學家稱氣候變化導致猛馬像滅絕
更新時間 2010年 8月 18日, 格林尼治標準時間15:03
猛馬像在大約4000年前完全滅絕英國杜倫大學科學家提出的最新理論認為，導致猛馬像在大約一萬年前滅絕的原因是氣候變暖。
身被長毛的猛馬像曾經生活在歐洲的廣大地區，但是在大約14000年前向北遷移，撤退到西伯利亞北部地區，最後在大約4000年前完全滅絕。
有關猛馬像滅絕的原因曾出現激烈的爭論，有人說是氣候變化，也有人說是人類獵殺的結果，更有人把猛馬像滅絕的原因歸咎於小行星對地球的撞擊。
英國杜倫大學教授亨特利領導的研究小組用計算機模擬了過去42000年歐洲、亞洲和北美的植被變化狀況，認為現在可以為猛馬像的滅絕原因作結論了。
亨特利教授說，在21000年前的冰河期結束之後，氣候變暖，變濕，大氣中的二氧化碳濃度升高，樹木迅速生長，同時使得猛馬像賴以生存的草場顯著收縮，從而導致了猛馬像的滅絕。
http://www.bbc.co.uk/zhongwen/trad/world/2010/08/100818_mammoths.shtml
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