Tyrannosaurus (meaning “Tyrant Reptile”) was one of the most iconic of dinosaurs in ancient history. It appeared in fossil records at the very end of the dinosaur age in North America. With most estimation of its size set at 13 meters and weights of up to 8 to 14 metric tons, it is one of the most famous dinosaurs to be discovered and amongst one of the largest theropods known alongside with Giganotosaurus(14m), Mapusaurus(12.6m), Carcharodontosaurus(13m) and the largest theropod ever known, Spinosaurus(18m). Tyrannosaurus had small arms which were still functional and its large, powerful jaws were capable of producing one of the most powerful bite forces ever known. Since its initial discovery in 1900, Tyrannosaurus itself is known from a large variety of type specimens, including “Sue”, AMNH 5027, CM 9380, “Stan”, “Jane”, “Tristan”, “Wankel Rex”, “Black Beauty”, “Nanotyrannus”, “Trix”, “Victoria”, “Ivan”, “Bucky”, “Peck’s Rex” & “Scotty”. It is also known from 2 species, such as T. Rex(Which was from 66 million years ago during the Late Maastrichtian age of the Late Cretaceous) and the recently discovered T. Mcraeensis(Which lived 83.5 million years ago during the Campanian-Early Maastrichtian age of the Late Cretaceous).
North America, Maastrichtian Age of the Late Cretaceous, 66 Million years ago[]
66 million years ago, during the Late Cretaceous, North America was split in two by the Western Interior Seaway, forming the island continent Laramidea in the West. Tyrannosaurus fossils have been found in a wide range of habitats in western North America, including its famous locations: the Ojo Alamo/Javelina Formations of New Mexico & Texas and the Hell Creek Formation of Montana, North Dakota, South Dakota and Wyoming. There, it shared its ecosystem along with the three-horned Ceratopsians Triceratops and Torosaurus, the Hadrosaur Edmontosaurus, the armoured ankylosaurians Denversaurus and Ankylosaurus, Ornithomimus, and the dome headed Pachycephalosaurus, In the Javelina Formation, it lived alongside the 30.5-meter Titanosaurian Sauropod Alamosaurus and the large pterosaur Quetzalcoatlus. Tyrannosaurus possibly reached North america by evolving from it descendants, Guanlong and Yutyrannus from China as they gave rise to Tyrannosaurus itself and its close relative Tarbosaurus.
Competitors[]
Tyrannosaurus was the one of the largest carnivores of its range and may have filled different niches during its growth stages. Other predators include the much smaller Troodons and Oviraptorosaurs like Anzu which may have been omnivorous, the 6-meter Dromeosaurid Dakotaraptor and in the Western Interior Seaway coasts of North America, T-Rex had some competition from other Apex Predators such as the large Azhdarchid Pterosaur Quetzalcoatlus as well as even the Mosasaurs(Such as Tylosaurus). Because of all these facts, The Tyrant Lizard King itself continues to live on through the imagination of many others.