Life-Finding Expeditions

Despite living in an environment with no light, no oxygen, and very few nutrients, the microbes, which appear to survive on a low-calorie hydrocarbon diet, were abundant. The source of their food is the ancient coal bed system that is buried at this depth. Some microbes consume the coal itself, Trembath-Reichert noted, or smaller organic compounds associated with the beds, including methane and other hydrocarbons. Sure enough, in the lab, the researchers demonstrated that the collected microbes eat methyl compounds, which they process with their extremely slow metabolism. One question that remains is how these deep biospheres participate in the carbon cycle.

Up in the Arctic, marine biologist Antje Boetius of the Alfred Wegener Institute Helmholtz Center for Polar and Marine Research in Bremerhaven, Germany, and her colleagues navigated the Woods Hole Oceanographic Institution-built NUI through four Arctic dives, during which the vehicle snapped images of brown algae growing on the bottom of the ice, and giant crustaceans and tiny larvaceans swimming below. “It was the first time we could document such an abundance of life under the ice,” Boetius told Nature. The team next plans to use NUI to explore submerged regions of shrinking glaciers and ice shelves in the world’s polar regions.