Another meat-eating dinosaur, Allosaurus had a unique skeleton. Instead of having ribs that were attached to other bones in its body, this dinosaur had ribs that were attached to its skin. Its vertebrae were different too; the bones in its back were bulky and heavy. Standing at a height of over sixteen feet and weighing over one ton, this predator was the biggest carnivore around. Even though it had short arms, its hands had sharp claws for catching plant-eating dinosaurs. Often, Allosaurus would hunt together in groups, making it easier to take down their prey. Living into its twenties, Allosaurus was an intelligent and fierce predator.