CHERSKY, Russia -- During the last Ice Age, shaggy mammoths, woolly rhinos and bison lumbered across northern Siberia. Then, about 10,000 years ago -- in the span of a geological heartbeat, or a few hundred years -- the last of them disappeared.
Many scientists believe a dramatic shift in climate drove these giant grazers to extinction.
But two scientists who live year-round in the frigid Siberian plains say man -- either for food, fuel or fun -- hunted the animals to extinction.
Paleontologists have been squabbling for decades over how these animals met their sudden demise. The most persuasive theories say it was humanity and nature: Dramatically warming temperatures caused a changing habitat and brought a migration of men armed with deep-piercing spears.
No one knows for sure what set off global warming back then -- perhaps solar activity or a slight shift in the Earth's orbit. But, in an echo of the global warming debate today, Sergey Zimov, director of the internationally funded Northeast Science Station, and his son, Nikita, say man was the real agent of change.
As the ice retreated at the end of the Pleistocene era -- the final millennia of a 1.8-million-year-long epoch -- it cleared the way for man's expansion into previously inaccessible lands, like this area bordering the East Siberia Sea. When humans arrived, they hunted not only for food, but for the fat that kept the northern animals insulated against the subzero cold, which the hunters burned for fuel, say the scientists.
The wholesale slaughter allowed the summer fodder to dry up and destroy the winter supply, they say. "You don't need to kill all the animals to kill an ecosystem," said the younger Zimov.
-- The Associated Press