CHELSEA (CBS Detroit) – Something ancient has been unearthed near Chelsea, Michigan.

Paleontologists from the University of Michigan spent the day digging up the bones of an adult woolly mammoth after a farmer came across it while at work in his field in Washtenaw County’s Lima Township.

At first he and a friend thought they’d hit a bent fence post.

Tweets from the Ann Arbor News showed the muddy, fossilized find Thursday afternoon:

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

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

[Chelsea Update also posted some pictures on their Facebook page, taken by photographer Burrill Strong]

Daniel Fisher, a professor at U-M and director of the Museum of Paleontology, told WWJ Newsradio 950 that he knew exactly what he had 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,” said Fisher, “and I recognized that and said ‘humm, I think we have a mammoth here.'”

Fisher said they were able to retrieve multiple bones from the site.

“We extracted this very nice skull and tusks and we found the jaw of the animal, various ribs and vertebra.”

Extinct for a minimum of 10,000 years, the woolly mammoth lived during the Pleistocene epoch, and was one of the last in a line of mammoth species. Boasting enormous tusks and looking a bit like a furry version of the modern-day elephant, the woolly mammoth did co-exist alongside people for a time, scientists say.

Fisher said there are only 10 similar sites in Michigan where a significant portion of a woolly mammoth skeleton was found. He says this one was likely 40 years old when it probably was killed by humans.

“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 – 13,000 years ago,” he said.

Fisher said study of the bones may shed light on when humans arrived in the Americas, a topic of debate among archaeologists.

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