Simple foraminifera flourish at the ocean's deepest point

Extreme water depths make it very difficult to sample the bottom of deep-ocean trenches. As a result, almost nothing is known about small sediment-dwelling organisms (meiofauna) living in these environments, which are among the most remote on Earth. During a study of western Pacific trenches (97000 m water depth), we discovered abundant foraminifera (shelled protists) living in the Challenger Deep, the deepest place (10,896 m) in the world ocean. The fauna is dominated by morphologically simple species with organic walls. These distinctive taxa seem to be characteristic of the deepest ocean depths.