New research reveals that archaea, specifically Bathyarchaeia, dominate the deep biosphere in marine sediments. Unlike bacteria that consume easy energy near the surface, these archaea prioritize cellular maintenance over growth, allowing them to break down complex organic carbon over geological timescales. This process significantly impacts global carbon cycling. Findings suggest that these microorganisms mediate a large portion of organic carbon degradation after burial, acting as a critical regulator for how much carbon remains stored in the earth's subsurface.
