Ancient Shark Unearthed in World's Longest Cave System

Macadens olsoni had a unique curved row of teeth, called a tooth whorl. (Image credit: Art by Benji Paysnoe)

A remarkable discovery at Mammoth Cave in Kentucky has brought to light an ancient shark species, Macadens olsoni, which roamed the Earth approximately 340 million years ago. This significant find, announced by the National Park Service, offers new insights into prehistoric marine life.

Macadens olsoni was a small shark, measuring less than 1 foot (30 centimeters) in length. Its most distinctive feature was a curved row of teeth, known as a tooth whorl, specifically adapted for crushing its prey, likely mollusks and worms.

The fossilized remains were extracted from the Ste. Genevieve rock formation within Mammoth Cave, dating back to the Carboniferous period. During this era, the rocks of Mammoth Cave, formed between 320 to 360 million years ago, were submerged under a shallow saltwater body known as the Mississippian Sea. The cave system itself is a much more recent geological formation, having developed about 10 to 15 million years ago.

The genus name "Macadens" pays homage to Mammoth Cave, while the species name "olsoni" honors Rickard Olson, a retired park scientist whose efforts were crucial in documenting these fossils. This discovery is a vital addition to our understanding of ancient marine ecosystems, suggesting that the area preserved within Mammoth Cave may have once resembled thriving reefs. The unearthing of Macadens olsoniunderscores the immense value of preserving and studying natural history, revealing glimpses into the planet's distant past.

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Source:

• Live Science: "Ancient shark discovered deep inside world's longest cave system" - https://www.livescience.com/animals/extinct-species/ancient-shark-discovered-deep-inside-worlds-longest-cave-system