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 that man —either for food, fuel or fun — hunted the animals to extinction. Palaeontologists 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. For the Siberian grasses to provide nutrition in winter, they needed to be grazed in summer to produce fresh shoots in autumn.
The hooves of millions of reindeer, elk and moose as well as the larger beasts also trampled choking moss, while their waste promoted the blossoming of summer meadows. 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.
North-eastern Siberia, one of the coldest spots on the globe, was dry and free of glaciers. The ground grew thick with fine layers of dust and decaying plant life, generating rich pastures during the brief summers. 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. They may also have killed for prestige or for sport. —AP