Early ornithischian dinosaurs: the Triassic record

@article{Irmis2007EarlyOD,
  title={Early ornithischian dinosaurs: the Triassic record},
  author={Randall B. Irmis and William G. Parker and Sterling J. Nesbitt and Jun Liu},
  journal={Historical Biology},
  year={2007},
  volume={19},
  pages={22 - 3}
}
Abstract Ornithischian dinosaurs are one of the most taxonomically diverse dinosaur clades during the Mesozoic, yet their origin and early diversification remain virtually unknown. In recent years, several new Triassic ornithischian taxa have been proposed, mostly based upon isolated teeth. New discoveries of skeletal material of some of these tooth taxa indicate that these teeth can no longer be assigned to the Ornithischia using unambiguous synapomorphies. The Triassic record of ornithischian… 

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TLDR
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