Minnesota Now Has A State Fossil! Here’s Everything To Know About It

This just in -- Minnesota now has a state fossil! This summer, the Land of 10,000 Lakes officially adopted a state fossil, adding to the list of official state symbols for Minnesota.

Everyone knows about the state bird (loon), state fish (walleye), state muffin (blueberry), and state flower (lady slipper), but Minnesota was one of only four states in the country that didn't have a state fossil. That is, until now.

Personally, when I think "fossil", I think of something like a Tyrannosaurus Rex, Brontosaurus, or Triceratops. You know, dinosaur bones.

The official state fossil Minnesota adopted isn't exactly a dinosaur, but it is a pretty huge prehistoric creature that admittedly makes sense to be the fossil representation of the North Star State.

Minneota Names An Official State Fossil In 2025

Smithsonian Magazine reports that there has been a growing campaign for Minnesota to name a state fossil for a few decades. They trace the effort back to the late 1980s, when a group of elementary school students proposed making a giant Ice Age era mammal Minnesota's state fossil.

The effort has been continued through the years, turned down by the Minnesota Legislature each year it was brought up. The Science Museum of Minnesota even picked up the torch on this effort back in 2021, holding a vote for what fossil should be the official Minnesota state fossil. The results of their vote overwhelmingly said one answer, which has now become a reality.

READ MORE: Places You Can Hang Out With Dinosaurs In Minnesota

The effort to name Castoroides ohioensis Minnesota's official state fossil was approved as part of the state legislature's efforts in the Spring of 2025, codified into Minnesota Statute, and went into effect on July 1.

So, what is Castoroides ohioensis? No, it isn't a woolly mammoth; it is commonly known as the giant beaver.

I know, you're thinking, "A giant beaver? Really?" It's cooler than it sounds.

What is a giant beaver? How is it tied to Minnesota?

So, the name is pretty self-explanatory. They're basically gigantic versions of the modern-day beaver from 10,000+ years ago.

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They are about the size of a "small bear", getting up to around 6-7 feet long and weighing anywhere from around 200 to nearly 300 pounds. Now, that's a big beaver! You can see a full-skeleton fossil on the State of Minnesota's website.

The Science Museum of Minnesota says nearly complete skeletons of these giant beavers have been found in both Minneapolis and St. Paul, and lived in an area that included the Twin Cities and Southern Minnesota during the last ice age.

There are even words in native languages for this creature, with Ċapa being the Dakota word and Amik being the word in Ojibwe.

Where can you see giant beaver fossils in Minnesota?

The Science Museum of Minnesota is one of two places with giant beaver fossils in the state. In addition, the Bell Museum at the University of Minnesota also has giant beaver fossils.