Polar bears may struggle to cope with hotter world

Published on Monday 1 March 2010 20:32

POLAR bears rapidly evolved their white fur and Arctic lifestyle as they adapted to an ice age environment. But they may not be able to survive the accelerated pace of man-made climate change, new genetic evidence suggests..

The evolution of polar bears has remained a mystery – because they live on ice, ancient fossils are very rare.

However, recent analysis of DNA has revealed important clues about the origins of polar bears.

Study leader Dr Charlotte Lindqvist, from the University at Buffalo, in New York State, said: "Our results confirm that the polar bear is an evolutionarily young species that split off from brown bears some 150,000 years ago and evolved extremely rapidly during the late Pleistocene, just before the last interglacial period."

But polar bears as a species may prove less adaptive than their brown bear ancestors, Dr Lindqvist believes.

"The polar bear may be more evolutionarily constrained because it is today very specialised; living on the edge of the Arctic ice, subsisting on a few species of seals," she added.