Glaciers once inched toward the sea, gouging rocks. When the ice masses melted, they infused oceans with nutrients that may have shaped how life evolved, a study found.

Imagine floating in space, gazing on a frozen white orb. The ball hangs in the void, lonely and gleaming in the light from its star. From pole to equator, the sphere is covered in a thick crust of ice.

Around 700 million years ago, Earth was a very different planet—gripped by extreme deep freezes during the Cryogenian period. Enormous glaciers, kilometers thick, stretched across vast regions, turning much of the planet into a frozen wasteland.

Glaciers once inched toward the sea, gouging rocks. When the ice masses melted, they infused oceans with nutrients that may have shaped how life evolved, a study found.

During the Cryogenian, our planet was plunged into a series of deep freezes when enormous glaciers flowed across the globe. In new research published in Geology, we show that these crushing rivers of ice,