Was Earth born with life already on it?
Rather than life arising on Earth, did it already exist in space prior to our planet’s formation?
“When you arise in the morning, think of what a precious privilege it is to be alive — to breathe, to think, to enjoy, to love.” –Marcus Aurelius
If you asked a professional — a biologist, a fossil-hunter or a geologist — how old life on Earth was back in the 1970s, you would’ve gotten a very careful “I don’t know” answer. Going back before the rise of mammals, before birds, dinosaurs, reptiles, fish, crustaceans or even starfish and jellyfish — before the Cambrian explosion some 500–600 million years ago — we knew that Earth was inhabited. We knew we were a living planet, but the evidence was very scarce. While the past half-a-billion years or so provides a very rich fossil record, the way fossils form has an inherent limit to how far back we can see. Normally, animal corpses can get covered over by water, and by dirt deposits atop that water, creating the fossil record that we know, examine and study.
That’s sedimentary rock: the kind that contains fossils. But place too many layers of rock atop…
