Scientists Define New Limits of Microbial Life in Undersea Volcanoes
By some estimates, a third of Earth’s organisms live in our planet’s rocks and sediments, yet their lives are almost a complete mystery. The recent work of microbiologist James Holden of the University of Massachusetts-Amherst and colleagues shines a light into this dark world. In the journal Proceedings of the National Academy of Sciences, they report the first detailed data on methane-exhaling microbes that live deep in the cracks of hot undersea volcanoes.
“Evidence has built that there’s an incredible amount of biomass in the Earth’s subsurface, in the crust and marine sediments, perhaps as much as all the plants and animals on the surface,” says Holden. “We’re interested in the microbes in the deep rock, and the best place to study them is at hydrothermal vents at undersea volcanoes. Warm water there brings the nutrient and energy sources these microbes need.” The result will advance scientists’ comprehension of biogeochemical cycles in the deep ocean, he and co-authors believe.