Productivity and Community Composition of Low Biomass/High Silica Precipitation Hot Springs: A Possible Window to Earth's Early Biosphere?

ABSTRACT: Terrestrial hot springs have provided a niche space for microbial communities throughout much of Earth's history, and evidence for hydrothermal deposits on the Martian surface suggest this could have also been the case for the red planet. Prior to the evolution of photosynthesis, life in hot springs on early Earth would have been supported though chemoautotrophy. Today, hot spring geochemical and physical parameters can preclude the occurrence of oxygenic phototrophs, providing an opportunity to characterize the geochemical and microbial components. In the absence of the photo-oxidation of water, chemoautotrophy in these hot springs (and throughout Earth's history) relies on the delivery of exogenous electron acceptors and donors such as H₂, H₂S, and Fe²⁺.

SUBMITTER: Havig JR 

PROVIDER: S-EPMC6789502 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature