Gender-Specific Reproductive Tissue in Ratites and Tyrannosaurus rex

@article{Schweitzer2005GenderSpecificRT,
  title={Gender-Specific Reproductive Tissue in Ratites and Tyrannosaurus rex},
  author={Mary Higby Schweitzer and Jennifer L. Wittmeyer and John R. Horner},
  journal={Science},
  year={2005},
  volume={308},
  pages={1456 - 1460}
}
Unambiguous indicators of gender in dinosaurs are usually lost during fossilization, along with other aspects of soft tissue anatomy. We report the presence of endosteally derived bone tissues lining the interior marrow cavities of portions of Tyrannosaurus rex (Museum of the Rockies specimen number 1125) hindlimb elements, and we hypothesize that these tissues are homologous to specialized avian tissues known as medullary bone. Because medullary bone is unique to female birds, its discovery in… 
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