Craniofacial ontogeny in Tyrannosauridae (Dinosauria, Coelurosauria)

  title={Craniofacial ontogeny in Tyrannosauridae (Dinosauria, Coelurosauria)},
  author={Thomas D. Carr},
  journal={Journal of Vertebrate Paleontology},
  • Thomas D. Carr
  • Published 14 September 1999
  • Geography, Environmental Science
  • Journal of Vertebrate Paleontology
ABSTRACT A study of ontogenetic variation is used to clarify aspects of tyrannosaurid taxonomy and investigate the supposed phenomenon of dwarfism in the clade. A hypothetical ontogenetic trajectory is described for the relatively well-represented taxon Albertosaurus libratus. The type specimen of the purported “pygmy” tyrannosaurid Nanotyrannus lancensis was compared with specimens of A. libratus and found to share many morphological characters that exemplify immature specimens of the latter… 

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