Rock-eating bacteria

 Scientists have confirmed the presence of an array of microorganisms, including an extensive family of rock-eating bacteria, living in a subglacial lake in Antarctica. The discovery gives hope to scientists who suggest life could still be lurking deep under the surface of Mars.
Lake Whillans is buried under 2,640 feet of ice. It's primarily fed by the lower portion of the Whillans Ice Stream in West Antarctica, but is part of a vast subglacial drainage network -- a drainage system that scientists now know supports life. While it's fed with ice from above, the lake is made possible by melting from geothermal heating from below.
Researchers made similar findings 20 years ago in another nearby subglacial lake. But the scientists then hadn't come looking for life, and because their microorganism-containing samples had melted and were later refrozen, the validity of their discovery was called into question.
"People weren't really thinking about ecosystems underneath the ice," Louisiana State University biologist Brent Christner told Discovery News. "The conventional wisdom was that they don't exist, it's a place that's too extreme for this kind of thing,"
But Christner and his colleagues did go looking for life -- and they found it, 3,931 microbial-species-worth. The majority of the species, including the rock-eating bacteria, derive their energy from inorganic compounds like ammonium, nitrate, http://imgur.com/YAQclry and others.
"The action of the ice sheet pulverises the rock bed, and the mineral particles then go into the water where they become available for chemical and biological alteration," Christner told BBC News.