Stephen Giovannoni and his colleagues have discovered colonies of bacteria thriving beneath one of the coldest, driest deserts on Earth–the McMurdo Dry Valleys of Antarctica.

The find suggests that it’s possible life also exists in the inhospitable climate of Mars. The average temperature in the McMurdo Dry Valleys is about 68 degrees below zero. Within that frigid environment are warmer pockets where a combination of minerals, water, and solar radiation supports a surprisingly vigorous population of bacteria.

Giovannoni and OSU oceanographer Martin Fisk also have discovered evidence of rock-eating microbes living nearly a full mile beneath the ocean floor in the Pacific, Atlantic, and Indian oceans.

What these discoveries have in common are to primitive processes that were undertaken to create a simple, basic life form. These processes may have taken place hundreds of millions of years ago on Earth and may be taking place right now on Mars or Europa, one of the moons of Jupiter, Giovannoni said.

“It’s been suggested that Mars is too dry and cold for life to exist,” he said. “But it’s also known that both Mars and Europa have frozen water on or near their surfaces. It would be a distinct possibility that similar life forms could exist there.”

Giovannoni’s research team also has shown recently that one of the smallest known bacteria, SAR11, is also one of the most abundant organisms on Earth.

Dr. Giovannoni’s Department of Microbiology page
Dr. Giovannoni’s Center for Gene Research and Bacteriology page
SAR11 news release
Rock-eating microbes news release
Life in Antarctic ice news release