Allosaurus

Allosaurus was a fierce meat-eating dinosaur that roamed North America and Portugal around 155 million years ago. Its name means 'different lizard,' referring to its unusual backbone structure. This Jurassic predator left behind piles of bones in places like the famous Cleveland-Lloyd quarry.

• Had lightweight vertebrae that made its skeleton unique among dinosaurs.
• Lived during the late Jurassic period, 155 to 143 million years ago.
• Most fossils come from North America's Morrison Formation.