About 340 million years ago, a tiny shark swam in the waters of the world’s longest cave system in Kentucky, its unusual mouth curved in a way that will ultimately end up defining its future legacy.

Standing tall with her eyes cast to the sand, Candra Workman can spot a shark tooth smaller than a dime in under a minute. She draws a circle around it using her index finger. Crouching down, focusing ...

A new species of ctenacanth shark fossils was identified through fossils collected at Mammoth Cave in Kentucky. National Park Service As researchers continue to learn more about sharks that lurked in ...

Editor’s note: Every year, hundreds of undergraduates at the University of Delaware pursue research under the guidance of a faculty mentor. Such experiences provided by UD — a nationally recognized ...