A buried mountain range under Antarctica may have fed the first animals‘Supermountains’ Buried Under Antarctica Fueled Explosion of Life, Scientists Discover

For most of its first three billion years, Earth was a world of single cells. Then, around 538 million years ago, animals appeared — shells, eyes, legs, all of it, seemingly at once. Nobody has had a clean explanation for why.

There is a Himalayan range under the Antarctic ice

Two researchers at the Australian National University went after the rock beneath the Antarctic ice sheet. They dated 1,700 zircons, a mineral so tough it survives being recycled through mountains, and can be read like a timestamp of which continent it once belonged to.

What they found was a sudden glut of zircons from 650 to 450 million years ago — exactly when the supercontinent Gondwana was assembling. A range on the scale of the Himalayas stood there then, and its roots are still under the ice.

The mountains washed into the sea and became food

Mountains do not stand forever. Weather and water grind them down, and the debris — along with iron and phosphorus locked inside it — washes downriver into the ocean. For anything living in that water, it is an all-you-can-eat buffet nobody paid for.

With nutrients that abundant, single-celled organisms started clumping together, splitting up labour, and building hard shells. The authors put it plainly: it is unlikely to be a coincidence that the planet's most dramatic burst of evolution lines up with its most important stretch of mountain building.

Put simply, complex life did not take off because one worm got clever. It took off because a mountain range spent hundreds of millions of years quietly fertilising the sea.