Construction Crews Stumble Upon Mastodon Skeleton in Michigan

The massive animal was likely between 10 and 20 years old when it died roughly 12,000 years ago

Mastodon skeletons
Mastodon skeletons stand on display at the University of Michigan Museum of Natural History in Ann Arbor. WolfmanSF via Wikimedia Commons under CC BY-SA 4.0

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.

“We got a lot of vertebrae, a lot of ribs,” says Scott Beld, a paleontology research assistant with the University of Michigan, to MLive.com. “We got most of the leg bones. We got a lot of foot bones.”

The owner of the property where crews unearthed the bones has tentatively agreed to donate the skeleton to the Grand Rapids Public Museum. University researchers will lead the efforts to further study the bones, a process that will likely include analyzing the skeleton for a more exact date of death.

Then, researchers will clean and dry the bones for up to 18 months before putting them on display at the museum.

“It’s kind of unbelievable, just knowing that it was here this whole time,” says Courtney Clapp, whose family lives on the property, to FOX17’s Matt Witkos. “The guys and ladies here doing everything are doing a really great job at preserving everything.”

Mastodons and other large elephant-like mammals, including woolly mammoths, roamed North America during the Pleistocene Epoch. Indigenous peoples hunted the huge animals—which stood 8 to 10 feet tall and weighed 8,000 to 12,000 pounds—for food.

Researchers have unearthed the remains of hundreds of mastodons and woolly mammoths in Michigan, where the state’s many sediment-filled lakes and ponds helped preserve the bones for thousands of years. In 2015, a farmer near Chelsea uncovered the bones of a woolly mammoth. Then, in 2017, construction crews building a housing development south of Grand Rapids found mastodon bones. And last fall, a 6-year-old who was hiking with his family at a nature preserve in Rochester Hills stumbled upon a mastodon tooth.

Mastodon discoveries are so common in Michigan that, in 2002, lawmakers officially adopted the large, shaggy animal as the official state fossil.