Subterranean microbes get food from rocks

Science News : Deep within Earth, bacteria and other tiny organisms can coax the rocks around them to produce food, say researchers whose findings appear in the March issue of Geology. They have found that the mere presence of microbes triggers minerals to release hydrogen gas, which the organisms then ingest. “It looks like the bacteria themselves have an integral role in liberating this energy,” says R. John Parkes, a geomicrobiologist at Cardiff University in Wales. The work helps explain how microbes can survive up to kilometers deep in a subterranean world far from any sunlight to fuel photosynthesis.