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.
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