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Biology

Terror birds hunt South America

Flightless predatory birds up to three metres tall become apex carnivores on an isolated continent.

When
Duration
11 million years
Known to
± 2 million years
Era
Oligocene, Cenozoic

With no placental carnivores present, the top predator roles in South America go to marsupial sparassodonts and to the phorusrhacids — flightless birds with massive hooked beaks, powerful legs and reduced wings. Biomechanical work suggests they killed by striking downward with the beak like a pickaxe rather than by grappling. They hold those roles for tens of millions of years and decline only when North American carnivores arrive across the Panama land bridge.

Just before

Just after