fossil cretaceous creature that was first found in alberta canada
Albertosaurus
Albertosaurus
Albertosaurus (; meaning "Alberta lizard") is a genus of tyrannosaurid theropod dinosaurs that lived in western North America during the Late Cretaceous Period, about 70 million years ago. 
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Albertosaurus [SEP] Introduction
It may have been at the top of the food chain in its local ecosystem. While "Albertosaurus" was large for a theropod, it was much smaller than its larger and more famous relative "Tyrannosaurus rex", growing and possibly weighing or less. Since the first discovery in 1884, fossils of more than 30 individuals have been recovered, providing scientists with a more detailed knowledge of "Albertosaurus" anatomy than is available for most other tyrannosaurids. The discovery of 26 individuals at one site provides evidence of pack behaviour and allows studies of ontogeny and population biology, which are impossible with lesser-known dinosaurs.