Lake Vostok, buried under a glacier in Antarctica, is so dark, deep and cold that scientists had considered it a possible model for other planets, a place where nothing could live. However, work by Dr. Scott Rogers, a Bowling Green State University professor of biological sciences, and his colleagues has revealed a surprising variety of life forms living and reproducing in this most extreme of environments. A paper published June 26 in PLOS ONE (Public Library of Science) details the thousands of species they identified through DNA and RNA sequencing.
While Lake Vida, located in the northernmost of the McMurdo Dry Valleys of East Antarctica, will never be a vacation destination, it is home to some newly discovered hearty microbes. In the current issue of the Proceedings of the National Academy of Science, Nathaniel Ostrom, Michigan State University zoologist, has co-authored "Microbial Life at -13ºC in the Brine of an Ice-Sealed Antarctic Lake."
Once considered a barren plain dotted with hydrothermal vents, the seafloor and the crust beneath it are humming with microbial life -- with "dark energy," says Katrina Edwards of the University of Southern California, director of C-DEBI.
One single-celled organism from a hot spring near Mount Vesuvius in Italy fights uranium toxicity directly -- by eating the heavy metal and acquiring energy from it. Another single-celled organism that lives on a "smoldering heap" near an abandoned uranium mine in Germany overcomes uranium toxicity indirectly -- essentially shutting down its cellular processes to induce a type of cellular coma when toxic levels of uranium are present in its environment.
Though planets like these would be very different from Earth, this might not preclude them from being able to support alien life. "Scientists have found microscopic life forms on Earth that can survive all kinds of extreme conditions," Kane said. "Some organisms can basically drop their metabolism to zero to survive very long-lasting, cold conditions. We know that others can withstand very extreme heat conditions if they have a protective layer of rock or water. There have even been studies performed on Earth-based spores, bacteria and lichens, which show they can survive in both harsh environments on Earth and the extreme conditions of space."
Gases rising from deep within the Earth are fueling the world's highest-known microbial ecosystems, which have been detected near the rim of the 19,850-foot-high Socompa volcano in the Andes by a University of Colorado at Boulder research team.