Dinosaurs dying at the end of the Cretaceous Period. Volcanism is thought to be one of the main causes of the dinosaurs dying out.
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Courtesy of NSF

K-T Extinction (Why Did the Dinosaurs Go Extinct?)

Why did the dinosaurs go extinct? No one knows for sure, but there are some explanations that seem to make sense.

At the time the dinosaurs and lots of other species died out (which is sometimes called the K-T extinction), there were lots of active volcanos on Earth. There were also some large asteroids or comets that struck the Earth around then. Together, volcanos and asteroid impacts may have thrown dust into the atmosphere, blocking sunlight and making it very hard for the dinosaurs to survive.

Other things might have helped cause the dinosaurs’ extinction. We know that the atmosphere and the oceans both went through large changes at the end of the Cretaceous Period, and the Earth's climate probably changed a lot, too.

Scientists around the world are still doing research in order to test different theories and try to learn what made the dinosaurs go extinct.

Last modified March 25, 2010 by Jennifer Bergman.

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