Biological regulation of planetary atmospheres: A status report from the early Earth

Earth is currently our only known inhabited planet, n=1. Despite this unique (or not!) characteristic, we still lack fundamental knowledge of how Earth’s habitable environments developed, or how microbial life co-evolved alongside these environments. I will discuss new geochemical records of how biology regulated Earth’s early atmosphere, leading to the most dramatic change in Earth surface chemistry, the Great Oxidation Event (GOE). The GOE fundamentally altered the face of our planet, eventually allowing for the habitable biosphere we inhabit today. Notably, understanding how life evolved on this planet will inform our search for habitable planets in other solar systems.