Early Life Was Pumping Out Oxygen, But the Earth's Mantle Was Absorbing it

About 2.4 billion years ago, everything changed for Earth. That was the time of the Great Oxidation Event (GOE), when photosynthetic bacteria flooded the atmosphere with oxygen, banishing early, non-oxygen using lifeforms to the fringes of the Earth. The GOE laid the groundwork for the Earth we see today, dominated by complex, oxygen-breathing lifeforms. But …