SCIENTIFIC AMERICAN The planet’s spin may have mediated critical atmospheric oxygen When Judith Klatt began studying the colorful mats of primitive microbes living in a sinkhole at the bottom of Lake Huron, she thought she might learn something about Earth’s early ecosystems. Instead Klatt, a biogeochemist at the Max Planck Institute for Marine Microbiology in … More Early Earth’s Slowing Rotation Helped Oxygen Build Up