An early breath of oxygen

Researchers at MIT have demonstrated that oxygen gas may have been present on Earth hundreds of millions of years before its debut in the atmosphere, locked in submarine "oxygen oases." The team has published evidence that tiny aerobic organisms, akin to yeasts, may have evolved to survive on extremely low levels of the gas in this environment eons before the "Great Oxidation Event," the GOE, which occurred almost nearly 2.3 billion years ago and allowed aerobic life to thrive on land. The results might reconcile a split in the earth sciences community that arose with the discovery about a decade ago of oxygen-rich molecular fossils present in sedimentary rocks, hinting at much older oxygen-using life before the GOE.