Origins of Elusive 'Ghost Shark' Revealed

A 280-million-year-old skull of a so-called ghost shark has helped researchers determine exactly how chimaeras — mysterious, mostly deep-sea fish with wing-like fins and pointy snouts — are related to sharks, a new study finds. The ancient skull, belonging to the 4-foot-long (1.2 meters) shark-like fish Dwykaselachus oosthuizeni, was a rare find, as this animal's skeleton is made of cartilage, which rarely fossilizes, the researchers said. An anatomical examination showed that the an