Thursday, May 11, 2006
Mammoths Extinct Because of Climate Change, Not Indians
Not too many years ago, the Makah Indians of the Olympic Peninsula resumed the hunting of whales. There was a very loud and physical outcry from certain animal rights and anti-whaling groups. Old charges that humans were responsible for the extinction of North American mega-fauna—the woolly mammoth, among others—were resurrected, with claims that history would repeat itself. Humans, they said, would yet drive the Pacific Blue Whale to extinction—and the Makah people would be responsible. Anti-Indian sentiment reached levels, in the Pacific Northwest, not seen since the Boldt Decision, which awarded Indians a rightful share of the salmon fishing.
Law suits were filed. PETA—People for the Ethical Treatment of Animals—arose with a fury in protest. The whale hunt was surrounded with controversy. Demonstrations occurred, even attempts to physically destroy the whaling canoes. Paul Watson, the head of a group called Sea Shepherd, personally intervened with his ship, at least until the need for funds called him to the good life in the Los Angeles area. Demonstrators were arrested.
The Makah got their whale, to the satisfaction of indigenous groups all over North America. The population of the Pacific Blue Whale continues to expand. Various anti-whaling demonstrators moved on, some to be arrested in the recent crack-down on “eco-terrorists.”
And, according to a report in the current “Nature,” it turns out that early Indians did not cause the extinction of wooly mammoths; climate change did. This should have been obvious, since the numbers of elk, moose, and bison grew across the continent—all three species being much easier to kill than mammoths...
Humans cleared of killing off woolly mammoths
Last Updated Wed, 10 May 2006 14:13:18 EDT
CBC News
http://www.cbc.ca/story/science/national/2006/05/10/mammoth-extinct.html?print
Climate shifts, not over-hunting, killed off the woolly mammoth and wild horse, a carbon-dating study suggests.
What caused the animals to become extinct at the end of the last Ice Age more than 10,000 years ago has been one of prehistory's greatest whodunits. Biologists have often pointed the finger at over-hunting by expanding populations of humans.
But new radiocarbon dates give a more precise account of what happened at the time of the mass extinctions, and shift the focus to global warming.
Paleobiologist Dale Guthrie analyzed bone samples from bison, moose and humans, which lived through the extinction period, and from wild horse and mammoth, which did not survive. The more than 600 samples were recovered in Alaska and the Yukon. He also studied preserved samples of pollen from the period.
He found that by the time Homo sapiens started pushing into the region around 12,300 years ago, the wild horse had already died out and woolly mammoth were in decline.
Meanwhile, populations of bison, moose and white-rumped elk called wapiti were increasing, said Guthrie, professor emeritus with the Institute of Arctic Biology at University of Alaska, Fairbanks.
By analyzing pollen samples, he concluded that a naturally occurring shift in climate caused the animals to change their diet.
Like their modern cousins, the wild horses and the woolly mammoth of the past had a large intestinal pouch, or caecum, suited to feeding on low-quality forage on the steppe.
But as the frozen landscape thawed, higher-quality grasses started to grow. Those grasses were favoured by the bison and wapiti but were indigestible to the mammoth, Guthrie suggested.
His results were published in Thursday's edition of the journal Nature.
Copyright ©2006 Canadian Broadcasting Corporation - All Rights Reserved
Law suits were filed. PETA—People for the Ethical Treatment of Animals—arose with a fury in protest. The whale hunt was surrounded with controversy. Demonstrations occurred, even attempts to physically destroy the whaling canoes. Paul Watson, the head of a group called Sea Shepherd, personally intervened with his ship, at least until the need for funds called him to the good life in the Los Angeles area. Demonstrators were arrested.
The Makah got their whale, to the satisfaction of indigenous groups all over North America. The population of the Pacific Blue Whale continues to expand. Various anti-whaling demonstrators moved on, some to be arrested in the recent crack-down on “eco-terrorists.”
And, according to a report in the current “Nature,” it turns out that early Indians did not cause the extinction of wooly mammoths; climate change did. This should have been obvious, since the numbers of elk, moose, and bison grew across the continent—all three species being much easier to kill than mammoths...
Humans cleared of killing off woolly mammoths
Last Updated Wed, 10 May 2006 14:13:18 EDT
CBC News
http://www.cbc.ca/story/science/national/2006/05/10/mammoth-extinct.html?print
Climate shifts, not over-hunting, killed off the woolly mammoth and wild horse, a carbon-dating study suggests.
What caused the animals to become extinct at the end of the last Ice Age more than 10,000 years ago has been one of prehistory's greatest whodunits. Biologists have often pointed the finger at over-hunting by expanding populations of humans.
But new radiocarbon dates give a more precise account of what happened at the time of the mass extinctions, and shift the focus to global warming.
Paleobiologist Dale Guthrie analyzed bone samples from bison, moose and humans, which lived through the extinction period, and from wild horse and mammoth, which did not survive. The more than 600 samples were recovered in Alaska and the Yukon. He also studied preserved samples of pollen from the period.
He found that by the time Homo sapiens started pushing into the region around 12,300 years ago, the wild horse had already died out and woolly mammoth were in decline.
Meanwhile, populations of bison, moose and white-rumped elk called wapiti were increasing, said Guthrie, professor emeritus with the Institute of Arctic Biology at University of Alaska, Fairbanks.
By analyzing pollen samples, he concluded that a naturally occurring shift in climate caused the animals to change their diet.
Like their modern cousins, the wild horses and the woolly mammoth of the past had a large intestinal pouch, or caecum, suited to feeding on low-quality forage on the steppe.
But as the frozen landscape thawed, higher-quality grasses started to grow. Those grasses were favoured by the bison and wapiti but were indigestible to the mammoth, Guthrie suggested.
His results were published in Thursday's edition of the journal Nature.
Copyright ©2006 Canadian Broadcasting Corporation - All Rights Reserved
