Tyrannosaurus rex is the most famous dinosaur in the world. But when, and how did this type of dinosaur originate? That’s what’s going to be covered in this article. T .rex is a formidable predator of its kind, and the last in the group to evolve. It was the apex predator from Alberta to Texas 65 million years ago, in the Late Cretaceous Period.
Jurassic ancestors
Fossil remains called Guanlong are identified as the first tyrannosaur remains by paleontologists. It lived in China, about 160 million years ago, in the Middle Jurassic. Other remains called Stokesosaurus are also described as basal tyrannosaurs. Stokesosaurus relatively looks much more like an allosauroid from external views. However, its internal structures are reminiscent of Tyrannosaurus.
Emperor Dragons
Dilong, literally, ‘Emperor Dragon’, in Chinese, is a small basal tyrannosaur from the Early Cretaceous Period. It was covered in a coat of feathers, built not for flight, but for warmth. It lived in China 100 million years ago. A key difference between basal and later tyrannosaurs were the size of the arms. In early models, the arms were long with three fingers on each hand, while in the later versions, there were only two fingers, with tiny arms.
Arms Race
Since the Early Cretaceous period, tyrannosaurs and ceratopsians competed in an arms race. From the earliest evidence of coexistence, each has evolved with the other. This is a list of their evolutionary arms race. The tyrannosaurs are on the left, while the ceratopsians are on the right.
Asia
Dilong – Psittacosaurus
Raptorrex – Microceratops
Alectrosaurus – Asiaceratops
Alioramus – Bagaceratops
Tarbosaurus – Protoceratops
North America
Gorgosaurus – Montanaceratops
Suskityrannus – Zuniceratops
Albertosaurus – Centrosaurus
Daspletosaurus – Chasmosaurus
Tyrannosaurus – Triceratops
Why do they have tiny arms?
Tyrannosaurs had the strongest bite force of any dinosaur ever to exist. Its teeth were also designed for shattering bone. It seems that tyrannosaurs did not have much use for long arms and grasping, clawing hands. Over time, the need became so small that the arms were nothing but insignificant things adding to the animal’s already gigantic body mass.
Why is T-rex so famous?
Tyrannosaurus is also the most well-known dinosaur both to the public world, and in the fossil record. It has been known from fifty well-preserved fossils, with some even indicating traces of soft tissue. Also, it has portrayed in a lot of public media. T. rex is also the model for the dino in Google’s Chrome Dino Run. All of these factors make Tyrannosaurus the most famous dinosaur in the world.
Anay Ganesh 