The Tail of Tyrannosaurus: Reassessing the Size and Locomotive Importance of the M. caudofemoralis in Non‐Avian Theropods

  title={The Tail of Tyrannosaurus: Reassessing the Size and Locomotive Importance of the M. caudofemoralis in Non‐Avian Theropods},
  author={W Scott Persons and Philip J. Currie},
  journal={The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology},
  • W. Persons, P. Currie
  • Published 1 January 2011
  • Biology
  • The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology
Unlike extant birds and mammals, most non‐avian theropods had large muscular tails, with muscle arrangements similar to those of modern reptiles. Examination of ornithomimid and tyrannosaurid tails revealed sequential diagonal scarring on the lateral faces of four or more hemal spines that consistently correlates with the zone of the tail just anterior to the disappearance of the vertebral transverse processes. This sequential scarring is interpreted as the tapering boundary between the… 
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