for National Geographic News
The woolly mammoth is the rock star of Ice Age mammals. It's been immortalized in Stone Age cave paintings and carvings and in museum displays as the quintessential Ice Age animal.
How did this Ice Age icon evolve from an elephant-type species grazing in Africa to a highly specialized Arctic dweller?
Two researchers studying the fossil record of European and Siberian mammoths have traced the evolution of the woolly mammoth. The research has raised a few questions about current evolutionary theories.
"Our study has shown that the origin and evolution of the mammoth is not as simple as many have believed until now," said Andrei Sher, a paleontologist with the Severtsov Institute of Ecology and Evolution in Moscow. "The real story here is how much more complicated evolution is."
The evolution of woolly mammoths in Europe, said Sher, was not just a local response to environmental changes, but also involved a complex interplay with northern populations from Siberia.
Adrian Lister, a paleontologist at University College London, collaborated in the study. "With the woolly mammoth," he said, "we have an example of a fairly generalized elephant species living in a tropical climate evolving into a highly specialized, hairy Ice Age animal in the far North."
Lister said he and Sher conducted the study because they were interested in how a new species arises. "To put it very simply, does evolutionary change happen in bursts in local areas and then spread out to other regions," Lister asked, "or does it happen in gradual increments through time, with the species advancing everywhere?"
Lister and Sher are co-authors of a report on the study published in the November 2 issue of the journal Science.
The earliest known mammoths originated in southern and eastern Africa around four million years ago. They migrated north and dispersed widely across Eurasia, from Western Europe to Siberia.
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