Hidden deep below the ground, a vast ecosystem of tiny organisms is reshaping scientists’ understanding of how life can survive in some of the planet’s most inhospitable environments. A team of researchers uncovered a hidden, yet thriving, world of rock-eating fungi, worms, and tardigrades buried hundreds of feet beneath the Great Lakes region. The findings, published in The ISME Journal, identified 689 unique fungi species, including 13 newly described species, in drops of water that hadn’t seen the surface world in thousands of years. “The discovery opens a window into a world that is dark, ancient and almost entirely hidden—but is far from lifeless,” Quinn Moon, an environmental scientist at the University of Michigan (UM) and lead author of the study, said in a statement. Digging deep To examine life in the subsurface, the researchers behind the new study collected water from gas wells drilled into the Antrim Shale, a buried rock formation that stretches beneath much of the Great Lakes region. The wells reached depths ranging from 650 to 1,640 feet (198 to 500 meters).
Researchers discovered organic-rich rocks and water deep below ground, and it’s teeming with life, including fungi and other tiny organisms. © John Megahan, University of Michigan Isotopic dating traced the water all the way to the Ice Age, meaning that it likely came from the melting of ice sheets and was last in contact with the surface 11,000 years ago. As the glaciers melted, the water likely carried fungi and bacteria all the way down through porous and fractured rock layers. Once the microscopic organisms settled in cracks of the Antrim Shale, they began to feed on the organic material trapped in the rock.
