Ancient Shark Species That Lived 325 Million Years Ago Discovered in Mammoth Cave

Ancient shark species, that lived hundreds of million years ago, have been discovered by scientists in the world's longest cave system in the United States, according to reports earlier in February 2024. Prehistoric shark fossils were found by paleontologists in Mammoth Cave National Park in Kentucky.

The discovery revealed the remains of the long-dead animal belonging to a new shark species, called Troglocladodus trimblei and Glikmanius careforum.

Both T. trimblei and G. careforum were predatory animals that belong to the extinct order Ctenacanthus, whose members include fish that were known for their strong teeth and distinct spines on their dorsal fins. The ancient sharks existed more than 325 million years ago at a time long before dinosaurs dominated Earth and a period before the supercontinent of Pangea emerged approximately 300 million years ago.

The Mammoth Cave in Kentucky's Edmonson County has been called the longest cave system on Earth, with more than 400 miles of it being explored, according to the National Park Foundation. It is also one of North America's oldest tour attractions, including tour packages across the 10 miles of the cave available. Amid its known popularity, the Mammoth Cave was once submerged underwater, as re-confirmed by the recent discovery.

Two New Shark Species Discovered

Two new shark species have been discovered during an ongoing Paleontological Resources Inventory (PRI) at Mammoth Cave National Park. The identification of the extinct shark species was based on collected fossils from the said cave covering areas from Kentucky to northern Alabama, according to a February 1 news release by the National Parks Service (NPS). Based on available evidence, the two sharks potentially hunted "ancient near-shore habitats" that covered Kentucky and Alabama.

The PRI started in November 2019 after John-Paul Hodnett, an ancient shark specialist from the Maryland-National Capital Parks and Planning Commission, worked with the NPS to identify to assess the park's shark fossils. Based on previous surveys, scientists and park authorities have identified at least 70 species of ancient fish from more than 25 caves and cave passages in the Mammoth Cave system.

Mammoth Cave National Park

The Mammoth Cave National Park was once submerged in an ancient ocean. The U.S. Geological Survey (USGS) explained this is the case since sedimentary rocks that form the current park that we know today were produced from sediments. These chunks of solid material were deposited into the area where Mammoth Cave is situated and were submerged by the prehistoric ocean 330 million years ago.

In particular, the park is situated in the Central Kentucky Karst. The latter is a limestone belt extending from the states of southern Indiana through Kentucky and into Tennessee, according to the USGS. In addition to the movement of tectonic plates, weathering, erosion, and other natural factors could have also changed the landscape of the area from its previous marine environment.