Fossil found in Steele County identified as ancient cephalopod; is on display at Mayville State University – Grand Forks Herald

MAYVILLE, N.D. — When Jay Anderson saw the ripples contained within them, he knew there was something special about the pieces of rock detached from a boulder at his Steele County gravel pit. A few months later, these wrinkles were identified as an extinct cephalopod dating back hundreds of millions of years.

The fossil was found in May when the boulder was smashed by an excavator’s jackhammer. The trip has been great since then, he said, and there may be more fossils in the pit.

“I have been over this land 100 times,” he said. “I always keep my eye open for something. (…) We’ll try to collect them all.”

The fossil belongs to a cephalopod in the genus Endoceras, although the species is still unknown, said Michael Kjelland, an instructor of biology and agribusiness at Mayville State University. It dates to the Ordovician period of the Paleozoic era, approximately 485 to 444 million years ago. Instead of suction cups, it had 10 tentacles with sticky edges.

Kjelland determined the genus with help from Peter Larson of the Black Hills Institute and Javier Ortega-Hernández, an invertebrate paleobiologist and curator of invertebrate paleontology at the Museum of Comparative Zoology at Harvard University. The museum has its own Endoceras fossil.

Contributed by / Beth Swenson

Kjelland was approached about the fossil by Shelly Anderson, Jay Anderson’s wife and colleague at Mayville State. Kjelland deals with fossils, mostly from the Mesozoic era, and agreed to look at these fragments. He was busy working in the Badlands during the summer, so he wasn’t able to identify the cephalopod until later in the year. He had never seen anything like this before, although he had found ammonites, similar invertebrates, in the Badlands.

Both he and Jay Anderson said they wanted to see what else might be in the boulder where the Endoceras came from, but that would require the right equipment. Kjelland also wants to talk to the North Dakota state paleontologist to determine the uniqueness of the fossils.

“This is exactly the kind of future research we want to do in this area,” he said. “We have to go out and see if we can find more of it.”

For now, fossil fragments can be viewed at Mayville State’s Department of Science and Mathematics. It’s an interesting and different discovery in this part of the state, he said, because the boulder was likely moved to that location by a glacier over the years.

“We just don’t see a lot (of fossils) here in eastern North Dakota,” he said. “On this large, flat rock, you could see on one side where it had been pushed for miles and miles, because it was flat and smooth and the gravel had made grooves in it.”

Kjelland said the experience was interesting and he looks forward to what’s to come. He had no idea that something like Endoceras could be found in North Dakota and said other people might see something interesting on or in a rock in their field or pasture.

“One more thing you know might be there,” he said.

Anderson said he would be interested in having paleontology students help search for more fossils and get a hands-on education. He also encourages others to be more curious about what they see outdoors and share it with children who can become part of the next generation of paleontologists.

“If you’re somewhere else, turn the rock over and see if you can see anything on the back, or look at a weird-looking rock and take it home,” he said. “There might be something to it. You never know.

Otto is a regional reporter for the Grand Forks Herald.