4.5 Billion Years
Earth Forms
A molten ball of rock and fire. Definitely no life.
4.4 Billion Years
First Oceans
The crust cools; water vapor condenses into the first seas.
4.1 – 4.2 Billion Years
The “RNA World”
Primitive molecules start replicating. We find “biogenic carbon” trapped in ancient zircons from this era.
3.8 – 4.0 Billion Years
LUCA. The Last Universal Common Ancestor. A simple, single-celled organism that lived near deep-sea hydrothermal vents.
3.7 Billion Years
First Stromatolites
Microbes finally get “organized” enough to start building the layered, oxygen producing mounds we can see today.
About the Author
