Science, Tech, Math › Animals & Nature Gorgosaurus Facts Share Flipboard Email Print Sergey Krasovskiy Animals & Nature Dinosaurs Carnivores Basics Paleontologists Dinosaurs & Birds Herbivores Marine Reptiles Prehistoric Mammals Amphibians Birds Habitat Profiles Mammals Reptiles Wildlife Conservation Insects Marine Life Forestry Evolution View More By Bob Strauss Science Writer B.S., Cornell University Bob Strauss is a science writer and the author of several books, including "The Big Book of What, How and Why" and "A Field Guide to the Dinosaurs of North America." our editorial process Bob Strauss Updated November 18, 2019 Name: Gorgosaurus (Greek for "fierce lizard"); pronounced GORE-go-SORE-usHabitat: Floodplains of North AmericaHistorical Period: Late Cretaceous (75 million years ago)Size and Weight: About 30 feet long and 2-3 tonsDiet: MeatDistinguishing Characteristics: Large size; sharp teeth; stunted arms About Gorgosaurus In many ways, Gorgosaurus was your garden-variety tyrannosaur; not quite as big (or as famous) as Tyrannosaurus Rex, but every bit as dangerous from the point of view of smaller, herbivorous dinosaurs. What really sets Gorgosaurus apart among paleontologists is that this dinosaur has left an unusually large number of well-preserved specimens (from Dinosaur Provincial Park in Alberta, Canada), making it one of the best-represented tyrannosaurs in the fossil record. Gorgosaurus is believed to have occupied the same North American territory as another fairly generic tyrannosaur, Daspletosaurus, and some experts think it might really have been a species of yet another tyrannosaur genus, Albertosaurus. This confusion can be attributed to the fact that Gorgosaurus was discovered about 100 years ago (by the famous paleontologist Lawrence M. Lambe), at a time when much less was known about the evolutionary relationships and characteristics of theropod dinosaurs. One interesting analysis of the growth patterns of Gorgosaurus has concluded that this tyrannosaur had an unusually long "juvenile" phase, after which it underwent a sudden growth spurt (in the course of two or three years) and achieved its full adult size. This implies that juvenile and full-grown tyrannosaurs inhabited different ecological niches during the late Cretaceous period, and probably subsisted on different prey as well.