Tucker Bailey, 12, stands in ankle-deep water in Hale County, beaming from ear to ear and showing off his latest find. The creek he’s standing in is about 170 miles north of the Gulf of Mexico, but the object in his hand in unmistakable: a small, black shark’s tooth.

The fossilized tooth dates back about 83 million years to a time when most of Alabama was covered by shallow seas.

“This rock layer where we’re standing would have been the bottom of the ocean,” said Allie Sorlie, education outreach coordinator for the Alabama Museum of Natural History, which organized the fossil hunting trip.

“We would be completely covered by ocean here, kind of a shallow sea at that time.”

For more on the Alabama Museum of Natural History‘s Fossil Excursions, read the AL.com article!