Seafloor Microbes Abundant and Thriving....An Alternative Cradle for Life?

May 28, 2008 / Posted by: Daniella Scalice

Researchers from NAI’s Marine Biological Laboratory Team continue their study of the deep biosphere, reporting the latest results in this week’s Nature. This new study reveals that bacterial communities dwelling on ocean-bottom rocks are more abundant and diverse than previously thought, especially relative to the overlying water column. The microbes appear to “feed” on the oceanic crust through seawater–rock alteration reactions involving the oxidation and hydration of glassy basalt.

Astrobiologists hypothesize that shallow water, not deep water, may have cradled the planet’s first life; that the dark, carbon-poor depths offered little energy to emerging life. But the newfound abundance of seafloor microbes makes it theoretically possible that early life thrived – and maybe even began – on the seafloor. “Some might even favor the deep ocean for the emergence of life since it was a bastion of stability compared with the surface, which was constantly being blasted by comets and other objects,” suggests study author and NAI member Katrina Edwards in the University of Southern California press release. For images and resources, see NSF’s press page.