New Shark Species Found in Historic Caves That Connected North America and Europe 325M Years Ago

This period predates the formation of the supercontinent Pangea, suggesting a time when the continents we know today were part of one vast landmass. The National Park Service announced these findings, underscoring the significance of such ancient marine life being discovered far from current ocean boundaries.

According to the National Park Service, these species are believed to have reached lengths of 10-12 feet, comparable in size to the modern oceanic whitetip shark.

“When these creatures lived, the region that is now Kentucky was an ancient seaway connecting North America, Europe and Northern Africa,” Rick Toomey, a cave guide and Mammoth Cave paleontologist, told WBKO News.

This geological transformation highlights the dynamic nature of Earth’s surface and its impact on marine ecosystems, as noted by the National Park Service.

Its stable environment preserves fossils exceptionally well, allowing for detailed studies of prehistoric marine animals, including the two newly discovered shark species.

The National Park Service describes its branched teeth, which resemble tridents, emphasizing the unique dental adaptations that helped it thrive in its ancient marine habitat.

The National Park Service remarks on the significance of these finds, stating, “This set of cartilage fossil was the first of its kind for this genus of ctenacanth shark. Its jaw shape suggests it had a short head with a powerful bite for hunting smaller sharks, bony fish, and squid-like orthocones.”

This limitation demonstrates the delicate nature of paleontological sites and the need for careful management to preserve these invaluable windows into Earth’s past.

“He [Trimble]  looked up and pointed and said, ‘Hey! Is that one of the shark’s teeth?” Paleontologist Rick Toomey recounts. “We said, ‘Wow, that’s going to be a […] really interesting shark.’”

These discoveries illustrate the ongoing process of scientific exploration and its role in uncovering the history of life on Earth.

John-Paul Hodnett, a paleontologist  at the Maryland-National Capital Parks and Planning Commission who works with the National Park Service’s paleontology program said, “You have to crawl on your hands and knees for a quarter mile. And that hurts, for me, after a while.”

The National Park Service’s announcement in October of another significant find, Strigilodus tollesonae, further enriches the story of prehistoric marine biodiversity. The New York Post reports that this extinct shark species, more closely related to the modern ratfish than to contemporary sharks and rays, underscores the diverse evolutionary paths of marine creatures and the rich paleontological heritage preserved within Mammoth Cave National Park.

This species was a petalodont shark that inhabited the Earth approximately 337 million years ago. Petalodonts are an extinct order of cartilaginous fish related to the modern chimaera.

Discovered from teeth embedded in the cave walls, the shark is believed to have possessed teeth featuring a rounded cusp for clipping and an extended, ridged side for prey crushing, resembling the function of molars. Paleontologists hypothesize that Strigilodus tollesonae likely adopted a lifestyle akin to modern skates, predominantly feeding on worms, bivalves, and small fish.

The revelation of fossilized shark teeth in the cave walls led to the engagement of shark fossil specialist John-Paul Hodnett from the Maryland-National Capital Parks and Planning Commission. Collaborating with park rangers, Hodnett successfully identified multiple species of primitive sharks based on the teeth and fine spine specimens discovered within the cave passages.

These teeth exhibited a distinctive fan-like arrangement, featuring a central large tooth surrounded by three progressively smaller teeth, providing valuable insights into the dental structure of Strigilodus tollesonae.

This unique dental structure provides insights into the feeding behavior and ecological niche of Strigilodus tollesonae. The significance of this discovery is emphasized by Barclay Trimble, Mammoth Cave’s superintendent, expressing excitement about the announcement of the park’s first new shark species.

The findings encompass a spectrum of chondrichthyans, cartilaginous fish, occupying various ecological niches, ranging from sizable predators to diminutive sharks coexisting within the crinoid forest on the seafloor—an environment that served as their habitat. Continued discoveries likely await us in the future.