📸 A T. Rex and triceratops ready for battle
Measuring 40ft (12m) in length and weighing upwards of 14 tons, Tyrannosaurus rex was one of the largest and most powerful terrestrial predators in history. The most advanced in an 80 million year chain of tyrannosaurid evolution, T. rex had heavy, deep skulls reinforced with sutures, lightened by hollow chambers and lined with dozens of sharp teeth. Various mechanical studies of T. rex power place the "Tyrant Lizard King" firmly at the top of the charts. Measuring 40ft (12m) in length and weighing upwards of 14 tons, Tyrannosaurus rex was one of the largest and most powerful terrestrial predators in history. The most advanced in an 80 million year chain of tyrannosaurid evolution, T. rex had heavy, deep skulls reinforced with sutures, lightened by hollow chambers and lined with dozens of sharp teeth. Various mechanical studies of T. rex power place the "Tyrant Lizard King" firmly at the top of the charts.
📸 Barnum Brown, the first to discover a partial T. Rex skeleton. (Source: NPR)
Paired with its incredible power, T. rex also had some of the largest teeth of any carnivorous dinosaur, with the largest measuring 1ft (30cm). But the image we may have of what a T. Rex looked like is constantly evolving along with the other dinosaurs. We now know many theropods possessed feathers, including smaller tyrannosauroids such as Dilong and Yutyrannus. Recent evidence suggests that larger tyrannosaurids did not sport full-body feathers as adults, instead shedding them as they matured.
Most research suggests that T. rex and its fellow large tyrannosaurids (Gorgosaurus, Albertosaurus, and Tarbosaurus) both hunted and scavenged to meet the requirements for powering their huge bodies. Their prey was vast: among the other dinosaurs bearing tyrannosaurid bite marks are Ceratopsids and Hadrosaurs. Sauropods such as Alamosaurus, which overlapped with T. rex in North America, and Opisthocoelicaudia, which shared Asian landscapes with Tarbosaurus, may also have been tyrannosaurid quarry. There are even some bite marks found on other Tyrannosaurus, suggesting intra-species competition.
📸 The Wankel T. Rex in the process of being unearthed (Source: Museum of the Rockies)
Bite marks from conspecifics have been found on the skulls of large tyrannosaurids, suggesting they may have also bitten each other in dominance or reproductive interactions. It is possible some species were pack-hunters; the first known tyrannosaurid trackway hints at three animals traveling together. Other busted T. Rex myths include the idea of their bad eyesight. Despite popular depictions of poor depth perception, studies show that when compared to other giant theropods, tyrannosaurids had a wide postorbital skull which resulted in forward-facing eyes and acute binocular vision.
Studies suggest the great tyrannosaurids achieved their huge size through accelerated growth spurts. At the peak of its growth spurt, a young T. rex may have put on the better part of a ton annually. To support this massive body, the T. Rex spine had to contend with a tremendous amount of weight. The size and strength of the vertebrae were essential to providing support for this enormous predator, but the entire apparatus also had to allow for rapid changes in movement and critical striking speed.
📸 The Hell Creek Formation in Montana, a hotspot for T. Rex finds. (Source: Fay Ranches)
📸 Sue the T. Rex on display. (Source: Field Museum)
The Tyrannosaurus has a long history of study through which we can trace the history of dinosaur paleontology. Pieces and fragments were found as early as 1874, but it was in 1902 that famed and eccentric paleontologist Barnum Brown found a partial skeleton in Montana’s Hell Creek Formation. It was not until three years later that the beast was entirely excavated, by which time it had been named Tyrannosaurus Rex by Brown’s superior at the American Museum, Henry Fairfield Osborn. Brown continued his work searching out more T. Rex specimens, finding a complete skull in 1907, the final piece of his puzzle.
In spite of Brown’s initial success and multiple T. Rex discoveries, only a couple dozen partial skeletons have ever been found. After a long hiatus, Harley Garbani found another specimen in 1966, also in Montana, then in 1980 a rancher in South Dakota found a skeleton about 40% complete. Other discoveries followed in Alberta, but a more complete skeleton proved elusive until 1990, when Sue arrived.
Named for its discoverer Susan Hendrickson, Sue retains about 90% of its skeleton and remains one of the largest T. Rexes yet discovered. Its discovery caused a massive legal battle between the Black Hills Institute of which Hendrickson was a part, and Maurice Williams, who’s land the institute was digging on. Ultimately the FBI even impounded Sue during the legal proceedings, after which the victorious Williams sold the skeleton to the Field Museum in Chicago, where it can be viewed by the public today.
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