Tyrannosaurus was of the genus “ theropod dinosaur .“
The species Tyrannosaurus “rex” (rex meaning 'king' in Latin) lived throughout what is now western North America.
T. rex lived during the late Cretaceous period , about 85 million to 65 million years ago -- toward the end of the Mesozoic Era .
This was known as the AGE OF REPTILES.
During this time, the Earth was seismically active, and there were many volcanic eruptions. The supercontinent Pangaea had broken up and the subcontinents were drifting apart. There were no polar ice caps, the sea level was higher than it is now, and the climate was warmer.
These creatures lived at the same time: Triceratops (which was probably preyed upon by T. rex), Ankylosaurus (an armored herbivore), Maiasaura (a plant-eater), Edmontonia (a plated dinosaur), Anatotitan (a duck-billed dinosaur), Pachycephalosaurus (a crested, plant-eating dinosaur), Parasaurolophus (a duck-billed dinosaur), Quetzalcoatlus (a huge flying reptile, not a dinosaur), Corythosaurus (a helmet-crested, duck-billed dinosaur), Styracosaurus , and many other fascinating creatures.
Because he was a meat-eater and walked on two feet, it probably affected which foods he chose.
Tyrannosaurus rex may have been an apex predator , preying upon hadrosaurs and ceratopsians , although some experts have suggested it was primarily a scavenger . This question is still unsolved among paleontologists .