Ancient tooth that belonged to an American mastodon is discovered in Missouri ...

Ira Johnson is an 18-year-old explorer living in Missouri who made an astonishing find while walking along the Grand River – he discovered a fossilized mastodon tooth. 

Johnson noticed a 'big rock' near the water that seemed to be out of the ordinary and when he took it home, he realized it was an ancient tooth.

Researchers who analyzed the remains say it once belonged to an American mastodon that lived during the Pleistocene Epoch some 10,000 years ago.

Mastodons are ancient relatives of the elephants and mammoths that were thought to have been destroyed by humans, but recent DNA testing shows they went extinct long before.

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Ira Johnson is an 18-year-old explorer living in Missouri who made an astonishing find while walking along the Grand River ¿ he discovered a fossilized mastodon tooth

Ira Johnson is an 18-year-old explorer living in Missouri who made an astonishing find while walking along the Grand River – he discovered a fossilized mastodon tooth

Johnson shares the love of treasure hunting with his father and has been exploring rivers since he was about 5 years old.

'I usually find silver-plated spoons or just a bunch of junk really,' Johnson told FOX2now.com.

'When I was in there looking and I walked over to the water's edge and I saw the tooth and I didn't really think much about it because it looked just like a normal rock.'

Johnson spotted the tooth, thinking it was just a rock, and brought it home to show his father whose 'face brightened.'

The tooth is about the same size as a human hand and was confirmed to have belonged to an American mastodon by researchers at the University of Iowa

The tooth is about the same size as a human hand and was confirmed to have belonged to an American mastodon by researchers at the University of Iowa

Mastodons are ancient relatives of the elephants and mammoths that were thought to have been destroyed by humans, but recent DNA testing shows they went extinct long before

Mastodons are ancient relatives of the elephants and mammoths that were thought to have been destroyed by humans, but recent DNA testing shows they went extinct long before

The tooth is about the same size as a human hand and was confirmed to have belonged to an American mastodon by researchers at the University of Iowa.

Another young explorer found a jaw of a mastodon on a farm in southern Iowa last year.

The bone still has a row of teeth attached and is the second fossil to have been discovered on the farm in the last 30 years.

It is thought to have belonged to a young member of the prehistoric animal that may have stood up to seven foot tall and lived in ancient Iowa around 34,000 years ago.

Ira Johnson shares the love of treasure hunting with his father and has been exploring rivers since he was about 5 years old

Ira Johnson shares the love of treasure hunting with his father and has been exploring rivers since he was about 5 years old

This is the second Mastodon fossils in 30 years onsite, with the last discovered by the couple who own the farm while fishing on the property.

They have handed over the new bones to the University of Iowa (UI) and has asked to stay anonymous so fossil hunters do not visit their property.

Another young explorer found a jaw of a mastodon on a farm in southern Iowa last year. The bone still has a row of teeth attached and is the second fossil to have been discovered on the farm in the last 30 years

Another young explorer found a jaw of a mastodon on a farm in southern Iowa last year. The bone still has a row of teeth attached and is the second fossil to have been discovered on the farm in the last 30 years

The remains are now kept in a cupboard at the Trowbridge Hall at the University of Iowa.

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