Mammoths’ extinction attributed to abrupt climate change

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Mammoths went extinct because of abrupt climate change resulting from rapid and short warming events known as interstadials, a new research has claimed.

Using advanced ancient DNA analysis techniques, radiocarbon dating as well as geological records, researchers have arrived at a conclusion that interstadials were responsible for extinction of mammoths during the last ice age or Pleistocene (60,000-12,000 years ago).

The findings of team of researchers led by University of Adelaide and the University of New South Wales (Australia) contradicts previous theories which pegged extreme cold periods, such as the last glacial maximum, as the reason behind extinction of these giant animals.

Researchers arrived at the conclusion after detecting a pattern, 10 years ago, in ancient DNA studies suggesting the rapid disappearance of large species. Initially they believed that that these were related to intense cold snaps. However, as they analysed more and more fossil-DNA, and combined all the data derived from improved carbon dating and latest temperature records, they were surprised to find the opposite.

Researchers pegged rapid warming, not sudden cold snaps, as the cause of the extinctions during the last glacial maximum.

The research helps explain further the sudden disappearance of mammoths and giant sloths that became extinct around 11,000 years ago at the end of the last ice age.

“This abrupt warming had a profound impact on climate that caused marked shifts in global rainfall and vegetation patterns,” said University of Adelaide lead author and Director of the Australian Centre for Ancient DNA, Professor Alan Cooper.

Copper says that these abrupt warming events occurred even without involvement of humans and if we take into consideration modern human activities that are impacting global climate to a huge extent, the consequences could be more disastrous.

“It is important to recognize that man still played an important role in the disappearance of the major mega fauna species,” said fellow author Professor Chris Turney from the University of New South Wales. “The abrupt warming of the climate caused massive changes to the environment that set the extinction events in motion, but the rise of humans applied the coup de grace to a population that was already under stress.”

In addition to the finding, the new statistical methods used to interrogate the datasets (led by Adelaide co-author Professor Corey Bradshaw) and the new data itself has created an extraordinarily precise record of climate change and species movement over the Pleistocene.

This new dataset will allow future researchers a better understanding of this important period than has ever been possible before.

The findings of the study have been published in Science.