Scientist Sophie Newbury studies the "dead zone," a rock layer in Karoo Basin.
Courtesy of Robert Gastaldo, Colby College

Geologic Findings Undermine Theories of Permian Mass Extinction Timing
News story originally written on March 2, 2009

You probably know that dinosaurs are extinct. That means they are no longer alive today. Millions of years before the dinosaurs roamed the Earth, there were plants and other animals alive. There were fish, reptiles, insects and amphibians. They, like the dinosaurs, suffered a big event called the Permian Mass Extinction. This was the biggest extinction event ever in Earth's history!

Geologists thought they had found a layer in rock that showed this Permian Mass Extinction. This was a layer in the rock where there was a lack of plant and animal fossils. They even called the layer the "dead zone".

But recent work done in South Africa, where the best fossils records from the Permian time period are found, showed that this dead zone layer in this area of South Africa couldn't be a marker for the Permian Mass Extinction.

Science is about testing ideas. It's exciting to find that an idea is right, but sometimes scientists find out that an idea is wrong. Then, with even more knowledge in hand, it's back to the workbench to test new ideas!

Last modified June 11, 2009 by Jennifer Bergman.

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