One of the questions most often asked at Burpee Museum is “How do you know Jane was a girl?” You see “Jane” is the juvenile Tyrannosaurus rex discovered by field crews in 2001 and the star of the Museum’s Diary of a Dinosaur exhibit. “Jane” was named after Jane Solem, wife of Robert H. Solem, a major benefactor and lifetime member of the Museum.
Currently it is unknown if “Jane” the dinosaur was male or female. In fact, determining the sex of dinosaur specimens is a question that paleontologists have long been trying to find a method or skeletal indicator that would allow specimens to be defined as male or female.
Scott Persons, paleontologist at University of Alberta at Edmonton, Canada, has recently proposed a new idea that may allow the sex of some dinosaurs be determined. His most recent study, published in Scientific Reports, suggests that skeletal traits of some dinosaurs tails may show sexual dimorphism (a distinct morphological difference between males and females) and could be applied to other specimens.
Persons’ study examined two oviraptorosaurs, nicknamed Romeo and Juliet, that were found in Mongolia in the 1990’s and first described in 2001. Through this study differences in bones called chevrons at the base of the oviraptorosaurs tails were discovered. One specimen had longer chevrons with broader tips. Persons hypothesizes that males may have had longer chevrons with broader tips for increased muscle attachments, whereas chevrons in females may have been smaller to facilitate egg laying.
As Thomas Holtz, University of Maryland, has pointed out, it will be very interesting to see if these differences are borne out in further, larger studies of chevron shape of small to mid-sized dinosaurs.
Perhaps someday soon we will be able to confidently answer the question of ” Is “Jane” a boy or girl?”
To read more about Person’s study check out these resources: