March 26 (Bloomberg) — Tyrannosaurus rex’s ancestors once roamed Australia, according to researchers who said a bone discovery provides the first evidence the fearsome dinosaur’s predecessors lived in Southern continents.
The hip bone, which was found in Dinosaur Cove in Victoria state — about 220 kilometers (136 miles) southwest of Melbourne — was that of a tyrannosaur that lived about 110 million years ago, 40 million years before T. rex roamed the earth, researchers said in a Science study today.
The discovery disproves a previous theory that tyrannosaurs never lived in the Southern continents, and raises the question of why larger predators such as T. rex evolved only in the Northern hemisphere, said Roger Benson, a researcher at the University of Cambridge in the U.K. who led the study.
“This find has major significance for our knowledge of how this group of dinosaurs evolved,” Benson said in a statement. “Tyrannosaur fossils had only ever been found in the northern hemisphere before.”
The bone, measuring 30 centimeters (12 inches), probably came from a dinosaur that was about 3 meters (10 feet) long and weighed 80 kilograms (176 pounds), Benson said in the statement. T. Rex grew to 12 meters and weighed 4 metric tons, or 4,000 kilograms.