Oskin writes about the new study:
Scientists call it the dark biosphere, and it’s potentially one of the biggest ecosystems on the planet. Buried oceanic crust covers 60 percent of Earth’s surface. For the first time, researchers have pulled up pieces of the crust and examined the life within. In its rocks, microbial communities thrive, eating altered minerals for food, the study found.
“They’re gaining energy from chemical reactions from water with rock,” said Mark Lever, a microbiologist at Aarhus University in Denmark and lead author of the study, published in the March 15 issue of the journal Science.
“Our evidence suggests that this is an ecosystem that is based on chemosynthesis and not on photosynthesis, which would make it the first major ecosystem on Earth that is based on chemosynthesis,” Lever told OurAmazingPlanet. [Strangest Places Where Life Is Found on Earth]
While bacteria and other microbes have been noted in deep boreholes drilled into the seafloor, the discovery confirms the extent of the life within the oceanic crust, as well as the possibility of life on other planets, the study scientists said.
“I think it’s quite likely there is similar life on other planets,” Lever said. “On Mars, even though we don’t have oxygen, we have rocks there that are iron-rich. It’s feasible that similar reactions could be occurring on other planets and perhaps in the deep subsurface of these planets.”
This week, NASA scientists announced the discovery of the chemical ingredients for life in Mars rocks, including sulfur, nitrogen, hydrogen, oxygen, phosphorus and carbon. The discovery suggests Mars could have once supported microbial life, scientists said.
Life inside Earth
The microorganisms living in the seafloor are diverse, consuming hydrogen, carbon, phosphorus and other elements, but for this study, researchers focused on methane-producing and sulfur-reducing species. The bacteria get their sustenance from inorganic molecules created during the chemical alteration of rocks by water. After consuming their “food,” the microbes emit methane or hydrogen sulfide (rotten-egg gas) as waste.