This video presents a complete timeline of prehistoric sharks, tracing their origins back more than 400 million years. Viewers see how early, primitive species evolved into some of the most efficient ...

Deep beneath Kentucky’s rolling hills, in the dark reaches of Mammoth Cave National Park, paleontologists have unearthed the fossilized remains of two never-before-seen prehistoric shark species.

If current extinction trends continue, global shark populations will lose much of their variety, thereby threatening ecosystems where specialized species serve vital roles, researchers have found. In ...