The windswept peak of Socompa Volcano, on the border of Argentina and Chile, is not a nice place to visit. Parching winds scour the mountain's gravelly slopes, temperatures can swing from below freezing at night to more than 38 degrees Celsius during the day, and the scarcity of oxygen atop the more than 6,000-meter peak fends off all but the hardiest of mountaineers. You certainly wouldn't want to live there. That is, unless you happened to be a microbial community inhabiting the thin crust of soil covering loosely-packed gravel, and imbibing your nutriment from gases seeping up from the heart of the dormant lava cone.
"It just looks like the surface of Mars," says University of Colorado at Boulder microbial ecologist Steve Schmidt, of Socompa's lofty peak. "Up to about 5,000 meters, you'll see an occasional lizard maybe, but above that there's really nothing." But that didn't stop Schmidt, with ...
