By Gregory P. Wilson
Many of us think of extinction as a terrible process that strips us of amazing biodiversity. On one hand, that’s certainly true. It’s estimated that more than 99.9% of living things that once existed are now extinct! On the other hand, extinctions often benefit the survivors.
As a paleontologist with the Burke Museum and University of Washington, I examine the evolution and ecology of early mammals in the context of major events in the earth's history.
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| Dr. Wilson in the field. |
Marine fossils from around the world contain important clues to understanding this mass extinction event. But relevant terrestrial fossils, including dinosaurs, can only be found in a handful of places.
One of the most famous and intensively studied fossil sites is the Hell Creek badlands in northeastern Montana, where the type specimen of T. rex was discovered in 1902 by paleontologist Barnum Brown. In the 1980s, this area became a testing ground for the ‘Alvarez hypothesis’, which posited that an asteroid wiped out the dinosaurs in a geologic blink of an eye.



