Construction workers were replacing a culvert near Kent City, Michigan, last week when one of them spotted something red in the soil. Upon closer inspection, they realized it was a “humongous bone,” as Ken Yonker, Kent County drain commissioner, tells MLive.com’s John Tunison.

Based on the size of the fossils, the workers gleaned that they were not dealing with the remains of some ordinary farm animal. They called in the experts at the University of Michigan and the Grand Rapids Public Museum, who determined the bone belonged to a massive mastodon that roamed the Wolverine State some 12,000 years ago.

The find was unique because the mastodon was a juvenile, likely between 10 and 20 years old, per MLive.com. Though researchers have unearthed other mastodon skeletons in Michigan, those have mostly belonged to adults.

As news of the discovery spread, curious community members in west-central Michigan joined in on the excavation efforts, scooping up standing water in buckets and clearing away the muck and mud that encased the bones.

Since the construction crew found the bones on August 11, researchers and volunteers have filled 108 bags with various bones. They have not uncovered the animal’s skull or tusks, which means it’s unlikely the specimen could be re-assembled into a full skeleton.

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