KENT CITY, Mich. (WOOD) — Kent County road crews discovered prehistoric bones this week while digging along 22 Mile Road.

The crews were scheduled to replace a culvert along the county line to prevent water backup, but their excavation stopped when they found a three-foot-long femur.

“They assumed it was some sort of dinosaur bone,” Ken Yonker, Kent County drain commissioner, said.

Researchers from the University of Michigan later confirmed crews had discovered the remains of a mastodon. The prehistoric, hairy elephant was common in the Michigan area 12,000 years ago.

“We think it’s a young one mainly because the bones haven’t fused,” said Scott Beld, a research assistant at the Museum of Paleontology at the University of Michigan.

Beld said matriarchal mastodon herds typically kicked males out of their community around the age of 12 to 13. 

“What I thought [initially] was a femur and a tibia [discovered], but just in the last few minutes we’re looking at them and they may be two femurs and from the same side. If that’s the case we have two animals,” he said.

Once the bones are fully excavated, they will be processed through the University of Michigan. The landowners ensured that the bones will then return to the Grand Rapids Public Museum for the public to enjoy.