New Insights Into the Brain, Braincase, and Ear Region of Tyrannosaurs (Dinosauria, Theropoda), with Implications for Sensory Organization and Behavior

  title={New Insights Into the Brain, Braincase, and Ear Region of Tyrannosaurs (Dinosauria, Theropoda), with Implications for Sensory Organization and Behavior},
  author={Lawrence M. Witmer and Ryan C. Ridgely},
  journal={The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology},
  • L. Witmer, R. Ridgely
  • Published 1 September 2009
  • Biology
  • The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology
The braincase region of tyrannosaurs was investigated to provide insights on anatomical attributes relevant to inferences of sensory biology and behavior. CT scanning focused on three specimens of Tyrannosaurus rex, a juvenile Gorgosaurus, and the controversial Cleveland skull (CMNH 7541). Analysis shows that the cerebral hemispheres were enlarged, but conflicting information on the optic lobes suggests that brain conformation was not fully avian. Previous estimates of olfactory bulb size for T… 
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