MEET TYRANNOSAURUS REX Discovery and name The name Tyrannosaurus means ‘tyrant lizard’ in Greek, while rex means ‘king’ in Latin. Because the first discoveries of Tyrannosaurus were incomplete, it was once known under several different names, including Dynamosaurus and Manospondylus. Tyrannosaurus was named by the famous palaeontologist Henry Fairfield Osborn in 1905. Lived where and when? Tyrannosaurus rex lived in the Late Cretaceous (approximately 78-65 million years ago) in North America. Tyrannosaurus bones have been collected from Alberta, Saskatewan, Montana, North Dakota, South Dakota, Wyoming, Colorado, Utah, Texas and New Mexico. Super size and growth For a long time, Tyrannosaurus was considered to be the largest meat-eating dinosaur, measuring up to twelve metres long, four metres high and weighing over five tonnes! However, this size is surpassed by several other meat eating-dinosaurs, including Spinosaurus from Africa and Giganotosaurus from South America. Compared to humans, Tyrannosaurus rex grew fast and died young. By looking at the growth rings inside bones, it is thought that Tyrannosaurus grew in rapid spurts, with immature individuals putting on 2kg a day! The largest Tyrannosaurus known yet was 28 years old when it died. Where the bite meets the hype – feeding and fighting in Tyrannosaurus As if the size of Tyrannosaurus wasn’t scary enough, the mandibles of the ‘tyrant lizard’ were amongst the strongest jaws of all time! Tyrannosaurus was able to tear and bite through bone and flesh with a force three times stronger than the bite of an American alligator. Pieces of shattered bone have actually been found in the coprolites (fossil poo) of Tyrannosaurus! The jaws of Tyrannosaurus were so powerful that they’ve left marks on the bones of other dinosaurs, including the horns and hip bones of Triceratops, the spinal column and limb bones of duck-billed dinosaurs, and the leg bones of the small, fast-running Thescelosaurus. Some Tyrannosaurus skeletons have even been found with bite marks from other T. rex, including wounds with broken teeth stuck inside! Some juvenile tyrannosaur skulls bear bites marks from other juveniles. While some bite marks show signs of healing, some badly mangled specimens do not, possibly suggesting death and cannibalism from such fighting. 1/…1 .