POLAR DINOSAUR BONE-HISTOLOGY

We report on the bone microstructure of a hypsilophodont and an ornith omimosaur from the Early Cretaceous, Otway Group of Dinosaur Cove in s outh-eastern Australia, which at the time lay well within the Antarcti c Circle. Although subjected to the same environmental conditions, the dinosaurs exhibit different hone histology. The hypsilophodontid show s a continuous rate of bone deposition, while the ornithomimosaur has a cyclical pattern of bone formation. We interpret these varying patte rns of bone microstructure as a reflection of different growth strateg ies of these dinosaurs.