 Unlike some other groups of dinosaurs , neither genus was more common at higher or lower elevations than the other . However , Gorgosaurus appears more common in northern formations like Dinosaur Park , with species of Daspletosaurus being more abundant to the south . The same pattern is seen in other groups of dinosaurs . Chasmosaurine ceratopsians and hadrosaurine hadrosaurs are also more common in the Two Medicine Formation of Montana and in southwestern North America during the Campanian , while centrosaurine and lambeosaurines dominate in northern latitudes . Holtz has suggested this pattern indicates shared ecological preferences between tyrannosaurines , chasmosaurines and hadrosaurines . At the end of the later Maastrichtian stage , tyrannosaurines like Tyrannosaurus rex , hadrosaurines like Edmontosaurus and Kritosaurus and chasmosaurines like Triceratops and Torosaurus were widespread throughout western North America , while lambeosaurines were rare , consisting of a few species like Hypacrosaurus , and albertosaurines and centrosaurines had gone extinct ; however , they had thrived in Asia with species like Sinoceratops and Alioramus . 
