Ancient Helicoprion Fish Had Spiral-Toothed Jaw

 

The ancient marine animal Helicoprion had a bizarre spiral-toothed jaw. The fish was initially thought to be a species of shark, but researchers at Idaho State University have recently determined it was a type of ratfish. Using CAT scans and making 3-D virtual reconstructions of the jaws, they also determined the saw-like teeth were located in the back of Helicoprion's jaw. The scientists say the jaw created a rolling and slicing mechanism.

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