Although it's been dead since the end of the Cretaceous period, the towering Tyrannosaurus bataar inside the Arizona Museum of Natural History is still terrorizing smaller creatures, albeit of the Homo sapiens variety, with its frightening teeth, menacing presence, and roaring countenance. Toddlers sometimes skitter away from its petrified skeleton, despite the fact it hasn't moved on its own for more than 80 million years. Theropods like this fearsome killing machine are just one of more than a dozen fossilized bones on display in Dinosaur Hall, the museum's main attraction. Other ancient bones include those of the cow-like camarasaurus, the duck-billed iguanodon, and numerous examples of triceratops. Meanwhile, models of pterosaurs and pteranodons hang from the ceiling over in the Rulers of the Prehistoric Skies room. And Dinosaur Mountain, a three-story re-creation of a Triassic peak, is populated by growling animatronic versions of a pentaceratops, stegosaurus, and other scaly relics. It's like Mesa's own version of Jurassic Park, except without the deadly dangers of dinos running amok.