During the Ordovician life expanded in diversity tremendously. After a mass extinction event, the Devonian period began and fish flourished.
For nearly 4 billion years, the continents of Earth were a lifeless wasteland. But beneath the sea, our planet was teeming with life. Many strange creatures evolved, from eel-like conodonts to voracious cephalopods, until nearly all life was wiped out in our planet’s first mass extinction.
1/2 • 2019 • Nature