Geologic age: About 1.9 million years to 10,150 years old, Pleistocene Epoch
Region in Minnesota: Twin Cities area and Freeborn County, Minnesota
Fast fact: With its buck teeth and aquatic lifestyle, Castoroides ohioensis probably looked a lot like modern beavers. But you would have noticed at least one big difference: weighing over 200 pounds, Castoroides was the size of a small bear.
It might have “Ohio” in its Latin name, but fossil hunters found the Science Museum of Minnesota’s giant beaver specimen right here in St. Paul! In fact the giant beaver almost became Minnesota's state fossil back in 1988. Want to give it another shot at the title?
Vote for Castoriodes ohioensis
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