Tyrannosaur Fossils
Tyrannosaurs from the Late Cretaceous of northern North America include Albertosaurus, Daspletosaurus, and Gorgosaurus. Fossils of these tyrannosaurs can be found in the Judith River Montana and Formations in Alberta. All tyrannosaurs are related and are early relatives to the Tyrannosaurus rex which appears at end of the Cretaceous Period. All three of these tyrannosaurs are smaller to Tyrannosaurus rex. The Daspletosaurus and Gorgosaurus were similarly sized and lived together during the same time. They are approximately 30 feet long and weighed up to 5000 lbs. Albertosaurus had a similar length of up to 30 feet but were lighter with a maximum weight of 4000 pounds. Albertosaurus appears to be evolved slightly later than its two Judith River Formation tyrannosaur relatives
Albertosaurus, Daspletosaurus, and Gorgosaurus teeth of similar sizes and designs make identification of isolated teeth near impossible. Daspletosaurus would be slightly larger than the other two Tyrannosaurs, and it was in the same sub-family as Tyrannosaurus rex. So, Daspletosaurus is more closely related to Tyrannosaurus rex and may have had tooth characteristics more like Tyrannosaurus rex. Albertosaurus teeth are typically smaller and thinner since they would be used for slicing prey. These tyrannosaur teeth from the Late Cretaceous of northern North America are high-quality and exceptional teeth and are fantastic examples of an early relative of Tyrannosaurus rex.