Award: OCE-1062006

How did life get here? What happened along the way? Why is life so diverse on our planet? Why doesn’t life look the same everywhere? These wide-ranging questions focused on the origins and diversification of life are fundamental questions for all of biology, from understanding why microbes in the human gut vary across individuals to monitoring virulence and the spread of disease to determining the earliest origins of life on our planet. Our research addresses some of the most central questions about the nature and extent of life on Earth in one of its least explored corners, the deep ocean. Our focus is on microorganisms, who for more than three billion years have served as engines of Earth’s biosphere, driving essential biogeochemical cycles that shape planetary habitability.

The global ocean comprises Earth’s largest microbiome, with at least half of the ocean’s microbial biomass occurring beneath the ocean floor. The focus of this study is the largest actively flowing aquifer system on Earth- the fluids circulating through oceanic crust underlying the oceans and sediments. There is a vast flow of fluid exchanging between ocean basins and crustal reservoirs and mediating transport of heat, solutes, genetic material, microorganisms, and viruses.

In this study, we used recently installed subseafloor observatories to access life beneath the seaflor in the middle of the Atlantic Ocean. Results show that the microbial community in the fluids beneath the seafloor are active, diverse, distinct, and engaged in both heterotrophy and autotrophy. Future examination of samples collected from this study will provide more insight to the functional profiles and evolutionary trajectories of these unexplored communities.

Last Modified: 08/12/2015
Modified by: Julie A Huber