Winters 'wiped out whole population'

LONDON - Britain has been colonised at least eight times over the past 700,000 years and on seven of these occasions the entire human population was wiped out by intensely cold winters.

This is one of the main conclusions of a five-year investigation into the prehistoric sites of Britain which has shown that the last colonisation occurred less than 12,000 years ago - making Britain a younger country than Australia, which has been continuously inhabited for at least 50,000 years.

"Britain had to be repopulated over and over again. Completely new people had to come back, sometimes with a gap of 100,000 years between these occupations," said Professor Chris Stringer, head of human origins at the Natural History Museum in London.

"Early Britons had to cope with these changes of climate. Often they couldn't and they died out completely. Britain and the British people today are new arrivals. We're products of only the last 12,000 years," Stringer said.

Studies of several prehistoric sites have revealed that the early human inhabitants of Britain lived alongside large mammals such as elephants, mammoths, rhinos and hippos as well as fierce carnivores such as hyaenas and scimitar-toothed cats.

Over the past 800,000 years the climate has fluctuated widely from being semi-tropical to the freezing cold of an ice age.

On seven occasions the winters became extremely cold with average temperatures plummeting to well below freezing.

There was a severe cold spell between 12,000 and 15,000 years ago that seems to have wiped out all humans who lived here. Then there was an eighth wave of colonisers who crossed from the continent over a land bridge that connected Britain to the mainland.

"It looks like there have been eight separate colonisation events that we can record and seven of those were unsuccessful so it is only the one in the present interglacial that is a successful one that leads through to the present day," Stringer said.

There was one particularly cold period that seemed to have prevented people from living in Britain for about 40,000 years.

"We're talking about little windows of time when the climate was good enough for them to survive here, until we get to the late part of the story," he said.

At Lynford in East Anglia scientists have found evidence that Neanderthals lived in Britain and managed to cope with very cold winters with temperatures of minus -10C.

"The interesting thing is how were they surviving at Lynford. There are no trees there so the wind-chill factor alone must have been quite severe. They must have had shelters and some form of clothing," Stringer said.

However, this population was eventually wiped out. Ultimately, the Neanderthals were replaced by anatomically modern humans, Homo sapiens, who became the ancestors of today's Britons.

- INDEPENDENT