Assessing A Subsurface Hydrothermal Biosphere in Yellowstone National Park
Eric Boyd, Montana State University Awarded from 2016
Hydrothermal systems integrate geologic processes at a planet’s surface with those from the deep subsurface, yielding an incredible array of geochemical compositions. Studies of extremophiles inhabiting such environments have provided key insights that have substantially informed our understanding of the habitability of Earth and other planetary bodies. While considerable evidence exists that describes the diversity and distribution of microorganisms in hydrothermal environments, little is so far known of the extent and nature of the highly reduced, subsurface hydrothermal biosphere. This is a key knowledge gap considering that such environments are likely to be more pertinent analogs for subsurface hydrothermal environments on other planets (e.g. Europa, Enceladus and Mars). Emerging evidence from our research group indicates the presence of an endemic subsurface biosphere in certain areas of YNP. Here we propose to determine the extent and nature of the YNP subsurface biosphere using novel, non-‐‑invasive techniques that will 1) use known geochemical proxies to link microbial composition and abundance data to a spring continuum of subsurface/surface fluid mixing and identify a subset of springs with the greatest evidence for subsurface-‐‑like characteristics, 2) use depth profiling experiments to provide further evidence for microbial population transitions from surface to deeper environments, and 3) determine the physiologic potential of ‘subsurface-‐‑like’ organisms using whole community genomics techniques. The results of this proposed work will serve to generate new hypotheses regarding the potential physiological adaptations that allow habitation of the deep hydrothermal biosphere, and which will be used in future NASA proposal efforts.
Microbiology and Immunology
Montana State University
Bozeman, MT 59717