The greening of the pre-Cambrian

The greening of the pre-Cambrian

It’s one of the biggest problems in the Earth’s history: What prompted the Cambrian explosion of multi-cellular animal life? (Though calling it the ‘Cambrian explosion’ is a misnomer at this point; most geologists agree that life took off a bit earlier than the Cambrian 540 million years ago — probably 50 million years or so before that boundary.)  … Read more