330-million-year-old shark head discovered in Kentucky

The region now known as Kentucky was once home to sharks, according to a new discovery. Researchers have discovered the remains of up to 20 prehistoric sharks in the Mammoth Cave National Park in Kentucky, a recent announcement has revealed. Among the findings was the 330-million-year-old head of a massive shark preserved in the cave's wall; its teeth are protruding from the limestone.

In Earth's very distant past, the landmass now known as North America was mostly covered with oceans. These oceans were home to large sharks, among other things, which would naturally die over time and become covered in sediment. Over the vast changes of this time period, the oceans retreated, the sediment became limestone, and entire cave systems formed.

The fossiled remains of these prehistoric sharks can be found embedded in the cave walls as a result, though finding teeth protruding from the limestone isn't a typical discovery. The newly found shark remains date back to the Late Mississippian period, shedding light on the sharks that existed during that sliver of Earth's history.

View this post on Instagram

Shark fossils of Mammoth Cave National Park

A post shared by John-Paul Hodnett (@desertsabertooth) on

Though preserved shark teeth aren't unusual, it is rare to find fossilized cartilage due to its softer nature. Scientists who investigated the new discovery found that part of the shark's head is preserved in the cave's wall, not just the teeth, including part of the jaw and chin.

The remains were first discovered by Mammoth Cave scientists, according to CNN, which reports that paleontologist John-Paul Hodnett was contacted with images of the discovery. Hodnett visited the site himself this past November and found that the discovery involved more than just teeth, also including parts of the shark's head.