Monday, November 26, 2012

'Diverse' Bacterial Life Found in Ice-Sealed Antarctic Lake


American researchers have found a "diverse" colony of microbial life living in an ice-sealed Antarctic lake. The life survives at temperatures of 8.6 degrees Fahrenheit and could mean that life could survive in extreme conditions on Mars or other places in the Solar System.

Life survives in Lake Vida, near the southern tip of Antarctica, despite the fact that the lake's waters are beneath more than 30 feet of ice, hadn't been uncovered for more than 2,800 years, and are about six times as salty as sea water.

Researchers initially discovered microbes frozen in the ice covering Lake Vida in 2002 and, during subsequent trips funded by the National Science Foundation and NASA in 2005 and 2010, sampled the lake's water. Researcher Alison Murray says what they found in brine samples was a "pretty diverse community" of microbes—with 32 types of bacteria falling under eight different phyla.

[RELATED: 'Fossil' Mountains Entombed by Ice]

"The diversity suggests it's a pretty sable community of interacting parts," she says.

It also might mean life could survive in environments that scientists once thought were inhospitable, such as Mars or Europa, a moon of Jupiter that scientists hypothesize might have subterranean oceans.

"This discovery gives us the indication that life can survive in such cold temperatures and isolated from surface processes," Murray says. "It has expanded our view of the types of ecosystems that are habitable."

[PHOTOS: Santas Parade Through Chilly NYC]

Murray's discovery, published in the journal Proceedings of the National Academy of Sciences Monday, is the latest in a series of new research in Antarctica. Earlier this year, Russian scientists announced they'd successfully sampled Lake Vostok, which had remained untouched beneath 2.5 miles of ice for more than 15 million years. If scientists discover life in Vostok, it is likely to look different than the bacteria inhabiting Lake Vida, Murray says.

Vostok's water is also kept in liquid form largely because of pressure exerted from the ice, whereas Vida's water remains in liquid form because of its high salt content. "On all accounts they're very different—Vostok is kilometers below the surface, we're meters below the surface. Vostok is also thought to have much more fresh water compared to Vida," she says.

No comments:

Post a Comment