This is an artist's recreation of Helicoprion, a 270-million year old shark that roamed the ocean preying on other marine life WITH ITS FULL 360-DEGREE SPIRAL BUZZSAW OF TEETH. Now? Now it's extinct except for in our nightmares starting tonight.
"When the animal closed its mouth on prey, the spiral of sharp teeth rotated backwards, like a circular saw, and slashed through the meat," lead author Leif Tapanila, an associate professor in the Department of Geosciences at Idaho State University, told Discovery News.
No living land or sea animal directly resembles Helicoprion -- especially it's buzz-saw tooth whorl.
"It was really an improbable animal, and maybe one of the best examples of a successful 'Hopeful Monster,'" Tapanila said, explaining that this refers to evolutionary processes that can result in very unusual body types, with most doomed to failure.
Oh man, I knew a kid in middle school who had really gnarly looking teeth like that. All the other kids used to make fun of him. Me, I'm talking about me. I had really thick bottle-cap glasses too. I actually had a college girlfriend break up with me when I showed her my old yearbooks.
Hit the jump for a fossil of the spiraling teeth.
Thanks to AngryKat and Acamori, who have both successfully wrestled sharks. You can tell because they're still alive to send tips.