
Science
The Great Oxidation Event: When Life Nearly Destroyed Itself
2.4 billion years ago, cyanobacteria flooded Earth with a toxic gas called oxygen, triggering the planet's first mass extinction and making complex life possible.
Casey Cooper·

2.4 billion years ago, cyanobacteria flooded Earth with a toxic gas called oxygen, triggering the planet's first mass extinction and making complex life possible.

In a remote corner of northern Quebec lies a rocky outcrop that dates back 4.16 billion years, the only surviving fragment from Earth's violent, molten youth.