The deep biosphere—the realm of sediments far below the seafloor—harbors a vast ecosystem of bacteria, archaea, and fungi that are actively metabolizing, proliferating, and moving, according a new study by scientists at Woods Hole Oceanographic Institution (WHOI) and the University of Delaware (UD).
"This is the first molecular evidence for active cell division in the deep biosphere," says Orsi. Previous studies and models had suggested cells were alive, but whether the cells were actually dividing or not had remained elusive.