Saws, Scissors, and Sharks: Late Paleozoic Experimentation with Symphyseal Dentition

@article{Tapanila2018SawsSA,
  title={Saws, Scissors, and Sharks: Late Paleozoic Experimentation with Symphyseal Dentition},
  author={Leif Tapanila and Jesse Pruitt and Cheryl A. D. Wilga and Alan Pradel},
  journal={The Anatomical Record},
  year={2018},
  volume={303}
}
Sharks of Late Paleozoic oceans evolved unique dentitions for catching and eating soft bodied prey. A diverse but poorly preserved clade, edestoids are noted for developing biting teeth at the midline of their jaws. Helicoprion has a continuously growing root to accommodate >100 crowns that spiraled on top of one another to form a symphyseal whorl supported and laterally braced within the lower jaw. Reconstruction of jaw mechanics shows that individual serrated crowns grasped, sliced, and… 
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