Farmer James Bristle came across a surprising find while digging in a soy field with a friend near Chelsea, Michigan -- the remains of a woolly mammoth.

"It was probably a rib bone that came up," Bristle told the Ann Arbor News. "We thought it was a bent fence post. It was covered in mud."

Eventually, researchers from the University of Michigan determined that Bristle had stumbled upon the bones of an animal that has been extinct for over 10,000 years.

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Daniel Fisher, a professor at the University of Michigan and director and curator at the university's Museum of Paleontology, told CBS Detroit that he knew exactly what it was when he saw the bones.

"I saw a part of a shoulder blade and there is a certain curve on a certain part of it that goes one way if it's a mastodon and another way if it's a mammoth," Fisher said. "I recognized that and said 'humm, I think we have a mammoth here.' "

Wooly mammoth found south of Chelsea, Michigan. pic.twitter.com/wnG4QLaelD — John Counts (@John_Counts) October 1, 2015

Fisher added that his team retrieved bones from the site, including a "very nice skull and tusks," ribs and vertebra, and the mammoth's jaw.

"It turns out we are dealing with carcass parts of animals , in some cases hunted, in other cases maybe not, but in any event, butchered by ancient humans, what we call Paleo-Indians -- people who lived in North America about 12 to 13,000 years ago," he said.

Wooly mammoth discovered south of Chelsea. pic.twitter.com/BzBguAXwix — John Counts (@John_Counts) October 1, 2015

Bristle's family bought the farm across from the mammoth site back in the 1950s, but it wasn't until about two months ago that he acquired this specific parcel of land. He was digging around to create lift station for a natural gas line.

He told Ann Arbor News that he new the find was "out of the norm," to put it mildly.

"My grandson came over to look at it, he's 5 years old, he was speechless," he said.

Local news site Chelsea Update also posted some pictures on their Facebook page.

The woolly mammoth lived during the Pleistocene era, and was one of the last in a line of mammoth species. Researchers say that the animal, with its enormous tusks and trunk, looked a bit like a furrier version of the modern-day elephant, and it actually co-existed alongside humans before its extinction.