Beneath 2,500 feet of ice at the South Pole, a 23-square-mile unfrozen lake flows in complete darkness under that immense mass of ice and snow. What's in that buried lake is even more surprising: life. Microbes thrive in this unbelievably inhospitable environment, feeding on chemical compounds released from crushed rock caused by erosion. New research by the University of Bristol details how different kinds of microscopic organisms survive on a previously unknown source of nutrients from ancient sediments. Their results were published this month in the journal Nature Communications Earth & Environment.