Posted on 07/24/2015 10:12:25 AM PDT by Red Badger
This image shows mammoth vertebrae in ice, Yukon Territory, Canada. Credit: Photo Kieren Mitchell, University of Adelaide
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New research has revealed abrupt warming, that closely resembles the rapid man-made warming occurring today, has repeatedly played a key role in mass extinction events of large animals, the megafauna, in Earth's past.
Using advances in analysing ancient DNA, radiocarbon dating and other geologic records an international team led by researchers from the University of Adelaide and the University of New South Wales (Australia) have revealed that short, rapid warming events, known as interstadials, recorded during the last ice age or Pleistocene (60,000-12,000 years ago) coincided with major extinction events even before the appearance of man.
Published today in Science, the researchers say by contrast, extreme cold periods, such as the last glacial maximum, do not appear to correspond with these extinctions.
"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.
"Even without the presence of humans we saw mass extinctions. When you add the modern addition of human pressures and fragmenting of the environment to the rapid changes brought by global warming, it raises serious concerns about the future of our environment."
The researchers came to their conclusions after detecting a pattern, 10 years ago, in ancient DNA studies suggesting the rapid disappearance of large species. At first the researchers thought these were related to intense cold snaps.
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Abseiling into Natural Trap Cave, Wyoming -- Professor Alan Cooper descending the 100ft pitch into the cave to excavate ice age megafaunal bones. Credit: Photo by Laura Weyrich, University of Adelaide
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However, as more fossil-DNA became available from museum specimen collections and through improvements in carbon dating and temperature records that showed better resolution through time, they were surprised to find the opposite. It became increasingly clear that rapid warming, not sudden cold snaps, was 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.
"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.
Explore further: Giant moa had climate change figured out
More information: Science, www.sciencemag.org/lookup/doi/10.1126/science.aac4315
Journal reference: Science
Read more at: http://phys.org/news/2015-07-mammoths-abrupt-climate.html#jCp
Quite possibly a meteor impact.......................
Catastrophism PinGGG!...............
It was the SUVs!
Which also became extinct
In a related story, PETA is suing “Abrupt C. Change” for the unlawful killing of Wooly Mammoths.
And they know it's "man-made" because?
Small brains.
Couldn’t build furnaces or houses.
Because Al Gore said so thats how we know. It is heresy to question Al Gore or Obama or any other liberals who spout the global warming theology.
Mammoths were climate change deniers....
Global warming froze them to death.
Haven’t we seen many periods of global warming during earth’s history? Weren’t all of the many ice ages in earth’s history ended due to global warming? And those periods of global warming had nothing to do with man. Unless we want to think that Cro Magnon Man had coal fired power plants .
It was a large SUV strike from the outer planets
that did it...
Not true! I saw a live one at the grocery store buying lobster and steak using her EBT card.
I doubt the meteor, there would be a crater, unusual layers of dust etc.
What should be more and more apparent is that dramatic climate change occurs when there was no fossil fuel burning, and minimal agriculture.
However, the relentless rise in CO2 is spooking the heck out of would be rational scientists.
The fear is, intervention on CO2 might be the opposite of what is needed for optimum climate. But of course, there is a school of thought that the “proper” number of humans should be around a billion. Optimum climate may be an ice age for these folks.
What hubris!!
Why do you think the libs want to stop teaching history? So we have no memory of these events.
To a liberal, history began at breakfast this morning.....................
Isn’t Mars atmosphere full of CO2?.....and it’s pretty cold there......................
Wooly Mammoths: They probably died of heat stroke....................
It's not the kind of place to raise your kids.
In fact it’s cold as hell..........
But there’s no liberals there to raise them, if you did.....................
LMAO!!
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