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Science
Prehistoric Shark Gallery Tour the Ancient Seas Make Your Own Shark
The American Museum of Natural History
The Search for Ancient Sharks
Helicoprion
Helicoprion lived about 250 million years ago. It belongs to a group of early sharks whose jaws evolved an elaborate buzz saw-like tooth whorl composed of successively larger replacement teeth, each one fixed to the tooth in front, forming an ever-growing spiral with the earliest (smallest) teeth at its center. This structure may have been used to injure or disable prey, which the shark could then eat at leisure. Helicoprion may have reached lengths over 10 feet, but many of its relatives were smaller and had less impressive tooth spirals.

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Helicoprion


 
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Picture: Ivy Rutzky |
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