Giganotosaurus
From Tardis Wiki, the free Doctor Who reference
The Giganotosaurus was a lesser known cousin of the Tyrannosaurus, over which it was half a ton heavier, several metres taller and with even more jaw strength. Its brain, though, was only half the size of that of a T-Rex, implying that the Giganotosaurus was an intellectual lightweight.
An adventurer confronted by a Gigantosaurus might have been able to escape becoming dinner by taking advantage of the Giganotosaurus by throwing a stone into a nearby bush or creating a bright pattern of flashing lights with a Sonic Screwdriver. (PROSE: Prehistory Repeating Itself [+]Loading...["Prehistory Repeating Itself (feature)"])