Nature and Extent of the Deep Biosphere

As investigators of life underground, we anticipate the chance to learn more about the unseen world of small life deep in Earth, but only if we continue to engage in essential collaborations with all those who possess complementary knowledge of the planet's history and systems. Soon, we hope, there will be more complete synthetic models of how the living and non-living aspects of Earth's uppermost layers function and integrate with one another. These models will guide our search for new deep life, its niches, capabilities, and adaptations. We look forward to new explanations for how the subsurface biosphere is sustained and how its expression matters to life at the surface.