What killed the dinosaurs? Few questions in science have been more mysterious—and more contentious. Today, most textbooks and teachers tell us that nonavian dinosaurs, along with three-fourths of all species on Earth, disappeared when a massive asteroid hit the planet near the Yucatán Peninsula some 66 million years ago.

But a new study published in the journal Geology shows that an episode of intense volcanism in present-day India wiped out several species before that impact occurred.

The result adds to arguments that eruptions plus the asteroid caused a one-two punch. The volcanism provided the first strike, weakening the climate so much that a meteor—the more deafening blow—was able to spell disaster for Tyrannosaurs rex and its late Cretaceous kin.

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