Ecologically distinct dinosaurian sister group shows early diversification of Ornithodira

@article{Nesbitt2010EcologicallyDD,
  title={Ecologically distinct dinosaurian sister group shows early diversification of Ornithodira},
  author={Sterling J. Nesbitt and Christian A. Sidor and Randall B. Irmis and Kenneth D. Angielczyk and Roger M. H. Smith and Linda Akiko Tsuji},
  journal={Nature},
  year={2010},
  volume={464},
  pages={95-98}
}
The early evolutionary history of Ornithodira (avian-line archosaurs) has hitherto been documented by incomplete (Lagerpeton) or unusually specialized forms (pterosaurs and Silesaurus). Recently, a variety of Silesaurus-like taxa have been reported from the Triassic period of both Gondwana and Laurasia, but their relationships to each other and to dinosaurs remain a subject of debate. Here we report on a new avian-line archosaur from the early Middle Triassic (Anisian) of Tanzania. Phylogenetic… 
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