Field in the frame: sampling the deep biosphere

Beneath the deep ocean floor may not seem like a natural place for a prospering ecosystem, yet microbial life can thrive in subsurface sediments. The International Ocean Discovery Program Expedition 385 led by Drs. A. Teske and D. Lizarralde set out to drill and sample the deep biosphere, at eight sites of the Guaymas Basin in the Gulf of California. Dr Edgcomb and colleagues analysed these data and found active microbial life across a range of sediment and temperature conditions, especially around hydrothermal structures. Their work demonstrates that subsurface microbial life can flourish, even in the most challenging of conditions.