Everett Claire Olson (November 6, 1910 – November 27, 1993) was an American zoologist, paleontologist, and geologist noted for his seminal research of origin and evolution of vertebrate animals. Olson identified a mass extinction that occurred 270 million years ago and which now carries his name - Olson's Extinction, also termed "Olson's Gap". Some of his other notable research also included genus of Slaugenhopia genus of Trimerorhachis, and genus of Waggoneria.
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