Dark Energy Supports “Alien Life” Beneath The Ocean Floor, Beyond The “Wildest Dreams”

Scientists have found that rocks beneath the seafloor are teeming with microbial life.

Credit: Nicolle Rager-Fuller/National Science Foundation

Once considered a barren plain dotted with hydrothermal vents, the seafloor and the crust beneath it are humming with microbial life–with “dark energy,” says Katrina Edwards of the University of Southern California, director of C-DEBI.

Seafloor and subseafloor bacteria not only exist, they’re more abundant and diverse than previously thought. The bacteria “feed” on the planet’s oceanic crust, posing questions about ocean chemistry and the co-evolution of Earth and life.

“We now know that this remote region is teeming with microbes, more so than anyone guessed,” says David Garrison, program director in NSF’s Division of Ocean Sciences, which funds C-DEBI.

While scientists have estimated that microbes living in deep ocean sediments may represent as much as one-third of Earth’s total biomass, the habitable part of the ocean crust may be ten times as great.

“Dark energy” is found in ocean depths: life abounds above and below the seafloor.

Credit: WHOI

Dark environments appeared to offer little energy for sustaining life. But the abundance of microbes in the subseafloor causes scientists to wonder how long life may have thrived there.

Researchers are working to answer such questions as:

What is the nature of subseafloor microbial communities, and what is their role in the alteration of young ocean crust?

Credit: IODP/USIO
Are these communities unique, especially in comparison with seafloor and sedimentary communities?

Where do microbes in the ocean crust come from–sediment, rock, seawater or another source?

A conference will be held next week directed at understanding thesubseafloor biosphere and its relationship to energy and material fluxes transported by fluid flow has the potential to answer questions about the evolution of life on Earth. This session provides an opportunity to hear results and ideas from various scientific disciplines.