|Lifespan||50 - 66|
|Medical Dart Resistance||158|
Unlocked by research in a Science Center
|Duration||06:00 - 06:40|
Albertosaurus was a relatively small tyrannosaurid from the Late Cretaceous Period, found in North America.Like other tyrannosaurids, Albertosaurus had a huge head with numerous large teeth, and a number of adaptations that allowed its skull to withstand the forces it exerted on its prey. Tyrannosaurids typically bit deeply into a carcass, then pulled back, and their serrated teeth were an indispensable tool in this motion. Tooth serrations lead, via what resembles a crack, to a round void known as an ampulla. These voids spread forces to a larger surface area on the tooth, lessening the risk of a crack developing. In addition to serrated teeth Albertosaurus had a strong skull with a fused nasal bone, and feet that could resist twisting motions as it tore at its prey.Based on the fossil evidence, Albertosaurus had a high mortality rate until it reached an age of around 2 years old, at which point it was the largest carnivore in its environment and no longer at risk of predation. At its peak Albertosaurus grew by 112kg per year. Albertosaurus, like other tyrannosaurids, was highly sensitive to smell and sound due to its large olfactory lobes and ear canals.
The first known Albertosaurus fossil consisted of a partial skull, discovered in June 1884, in the Red Deer River, Alberta, by the Geological Survey of Canada. A second skull was discovered in 1889. The team, not equipped with the proper tools to manage such a find, damaged the skull during its recovery.In 1892, the two skulls were assigned incorrectly to the existing species now known as Dryptosaurus. The specimens were determined to differ too greatly from Dryptosaurus and were given a new name, Albertosaurus, in 1904.In August 1910, a large group of Albertosaurus was partially excavated at another nearby quarry by American paleontologist Barnum Brown. Paleontologist Phil Currie resumed excavations in 1997 after he relocated the bone bed from photographic evidence.The number of individuals can be calculated from the number of unique skeletal elements found - if this estimate is used, the bone bed contained 12 unique Albertosaurus specimens. If instead we count skeletal elements that occur multiple times in one animal, but differ in size, there could be as many as 26. The large number of unique individuals found could be evidence of pack behavior, or the animals may have been brought together by a drought or flood.
The vast majority of fauna found in the Dry Island bonebed are dinosaurs; mainly hadrosaurs, ceratopsians, and ornithomimids. A wide variety of carnivores preyed on these dinosaurs, of which Albertosaurus would have been the apex predator. Fossil evidence suggests that Albertosaurus' habitat was semi-tropical, and rich in plant life.