Smithsonian Magazine on MSN

Sharklike fish with weird, buzz-saw jaws sliced through the seas, then vanished. Now, paleontologists are unraveling their secrets

The fossil whorls were a mystery. In 1899, geologist Alexander Karpinsky described an odd spiral of teeth, the first known fossil of its kind, uncovered from the ancient rocks of Krasnoufimsk, Russia.
insider.si.edu

Resurrecting the shark : a scientific obsession and the mavericks who solved the mystery of a 270-million-year-old fossil / Susan Ewing

Lasting impressions -- The shark bites -- Right shark, wrong name -- First, cousins -- Whorl of fortune -- Karpinsky makes the call : Helicoprion -- A shiver of sharks -- Signs of life -- The art of ...