Bacterium wakes up after 30,000 year sleep

A newly discovered life form that froze on Earth some 30,000 years ago was apparently alive all that time and started swimming as soon as it thawed, a Nasa scientist reported, in a finding he said has implications for possible contemporary life on Mars.

The organism - a bacterium dubbed Carnobacterium pleistocenium - probably flourished in the Pleistocene Age, along with woolly mammoths and sabre-tooth tigers, said Richard Hoover of Nasa's Marshall Space Flight Centre in Alabama.

Hoover discovered the bacterium near the town of Fox, Alaska, in a tunnel drilled through permafrost - a mix of permanently frozen ice, soil and rock.

"When they cut into the Fox tunnel, they actually cut through Pleistocene ice wedges, similar to structures that we see on Mars," Hoover said, adding that the discovery made it more likely that life could be found on Mars.