Those impacts in the early evolution of the Earth sterilized everything, life had to start over again from zero once the surface cooled. Actually might be wron

Those impacts in the early evolution of the Earth sterilized everything, life had to start over again from zero once the surface cooled. Actually might be wrong about that: "Three-dimensional computer models developed in May 2009 by a team at the University of Colorado at Boulder postulate that much of Earth's crust, and the microbes living in it, could have survived the bombardment. Their models suggest that although the surface of the Earth would have been sterilized, hydrothermal vents below the Earth's surface could have incubated life by providing a sanctuary for heat-loving microbes." https://en.wikipedia.org/wiki/Late_Heavy_Bombardment https://en.wikipedia.org/wiki/Late_Heavy_Bombardment Crazy. But that's only the most basic of microbes that would survive something like that.