The Mountains That Built Every Animal on Earth Are Buried Under Antarctica

Nearly half the sediment pouring into the oceans during the Cambrian explosion may have come from one vast mountain system in Antarctica. As those mountains eroded, they delivered phosphorus and iron into the sea just as complex animal life began exploding in diversity.

About half a billion years ago, nearly 20,000 kilometers of collision zones stretched across the assembled supercontinent of Gondwana. Continents were crushing into each other, building Himalayan-scale mountains and then shedding them grain by grain into the surrounding ocean.

The mountains are gone now. They eroded away so completely that little visible evidence remains beneath the ice covering 99.5 percent of Antarctica. But researchers at Australian National University traced their mineral fingerprints through seafloor sediments ringing the continent.

When Antarctica's contribution is added to the global geological record, the Gondwana mountain-building event becomes the largest known in Earth's history, dwarfing the formation of the Himalayas, Alps and Rockies.

The sediment carried phosphorus and iron into the oceans, nutrients that scientists think boosted marine productivity and oxygenation during the same interval when animal life was rapidly diversifying.

The mountains vanished half a billion years ago. The sediment kept the receipts.

Read the full story at Earth and Planetary Science Letters, September 12, 2026 (paywalled)

Hot Take: Imagine helping bankroll the Cambrian explosion and then getting eroded off the face of the planet.