Tyrannosaurs Rex fossil cast at the Royal Tyrell Museum (Pierre Camateros, cc-by-sa-3.0)
CBC Radio's Quicks & Quarks has a segment on the first pregnant Tyrannosaurus rex. Dr. Mary Higby Schweitzer, a professor in the Department of Biological Sciences at North Carolina State University, has confirmed that a 68 million year old T-rex, found in 2005, is, in fact, female and pregnant. The paper appeared in Nature Scientific Reports.
She and her team found medullary bone tissue in the dinosaur's femur. Medullary bone is found in modern female birds that are in the process of preparing to lay eggs. It is distinct in both its chemical composition and molecular structure from other bone.
Because birds are the modern relatives of dinosaurs, scientists assume medullary bone served the same purpose in T-rex. They hope that this discovery will help determine the sex of other Tyrannosaur fossils.
In the same show, another segment has an interview with Dr. Stephen Brusatte, a paleontologist from the School of Geosiences at the University of Edinburgh. He discusses Timurlengia euotica, a new tyrannosaur species that lived about 90 million years ago in Uzbekistan. The paper appeared in PNAS.
The new species - Timurlengia euotica - was as big as a horse, but the size and shape if its skull reveal that its brain and senses were already highly developed. It is believed that Timurlengia needed to become a smart predator with keen senses, before it could become the king of dinosaurs.
