dinosaur gender in science

["calzola@iol.it" <calzola@iol.it>]

"Gender-Specific Reproductive Tissue in Ratites and Tyrannosaurus rex"
Mary H. Schweitzer, Jennifer L. Wittmeyer, and John R. Horner
Science 3 June 2005: 1456-1460
ABSTRACT
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 extinct dinosaurs 
solidifies the link between dinosaurs and birds, suggests similar reproductive 
strategies, and provides an objective means of gender differentiation in 
dinosaurs

Filippo C



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