Researchers from Aarhus University in Denmark have carried out the first global analysis of the extinction of large animals during and immediately after the last Ice Age.
Image courtesy of Wikipedia.
Two of the leading theories as to the main cause for the extinction of large animals are climate change and overkill from human hunting.
The research team from Aarhus University wanted to find out if it was in fact due to climate change, humans or both.
In their study, the researchers produced the first global analysis and relatively fine-grained mapping of all the large mammals (with a body weight of at least 22 lbs) that existed during the period 132,000-1,000 years ago - the period during which the extinction in question took place. They were thus able to study the geographical variation in the percentage of large species that became extinct on a much finer scale than previously achieved, according to the Aarhus University News report.
The team determined that the correlation between climate change and the loss of large animals is weak and can only be seen in the Eurasia sub-region.
"The significant loss of megafauna all over the world can therefore not be explained by climate change, even though it has definitely played a role as a driving force in changing the distribution of some species of animals," said Postdoctoral Fellow Christopher Sandom of Aarhus University.
However, the researchers found a very strong correlation between the extinction of large animals and the history of human expansion.
"We consistently find very large rates of extinction in areas where there had been no contact between wildlife and primitive human races, and which were suddenly confronted by fully developed modern humans (Homo sapiens), said Professor Jens-Christian Svenning, Aarhus University.
"Our results strongly underline the fact that human expansion throughout the world has meant an enormous loss of large animals," says Postdoctoral Fellow Søren Faurby, Aarhus University.
The study has just been published in the article Global late Quaternary megafauna extinctions linked to humans, not climate change in Proceedings of the Royal Society B.
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