Sulfur-loving microbes may have been the party poopers of middle Earth. New research suggests that if such microbes dominated the oceans until half a billion years ago, the organisms could have contributed to the static period known as the “boring billion,” scientists report online September 28 in the Proceedings of the National Academy of Sciences. Various feedback loops involving biota and the nutrients they cycle could have maintained this stasis, creating an environment low in oxygen and unfriendly to multicellular life.
“If we really want to understand what’s happed in the history of Earth, we really have to understand this cross talk between the physical and biological processes,” says study coauthor Andrew Knoll of Harvard University.
Scientists have long wondered how the Earth remained in the geochemical and evolutionary stagnation that began about 1.8 billion years ago. The “Great