Science Story

03 December 2008 02:35 BST

Woolly mammoths 'originated' in North America

Surprising new research has declared that the last of the Woolly mammoths originated in North American.

The findings, published in Current Biology today, contradict previous thinking on the prehistoric animals which stated that specimens in North America were insignificant in the creature's evolution.

"Scientists have always thought that because mammoths roamed such a huge territory—from western Europe to central North America—that North American woolly mammoths were a sideshow of no particular significance to the evolution of the species," said Hendrik Poinar, from the McMaster University.

Researchers spent three years collecting and sampling mammoths' DNA from Siberia and North America and made a number of interesting discoveries.

"It now appears that mammoths established themselves in North America much earlier than presumed, then migrated back to Siberia, and eventually replaced all pre-existing haplotypes of mammoths," Mr Poinar said.

"Small-scale population replacements, as we call them, are not a rare phenomenon within species, but ones occurring on a continental scale certainly are," Ross MacPhee, curator of mammalogy at the American Museum of Natural History, added.

"We never expected that there might have been a complete overturn in woolly mammoths, but this is the sort of discoveries that are being made using ancient DNA."

Scientists had until now thought that North American woolly mammoths' contribution to the evolutionary history of the species was negligible.

The actual origin of mammoths is controversial in itself. Some scientists believe that the first proto-mammoths arose in Africa about seven-million years ago and then around five to six million years ago an early mammoth species migrated north into China, Siberia and then into North America.

This migration into North America led to the evolution of a new mammoth type - known as the Columbian mammoth.

Then in Siberia, a mammoth species adapted to the cold weather —the woolly mammoth - evolved and crossed into Alaska.

Scientists now believe that the Siberian mammoths began to disappear and were replaced by North American migrants.

"The study of evolution is an evolution in itself. This latest research shows we're drilling down and getting a closer and better understanding of the origins of life on our planet," Mr Poinar concluded.