Apatosaurus (or known as Brontosaurus, Meaning Deceptive Lizard) was a genus of a large sauropod dinosaur in the Late Jurassic Period. Its size protects it from predatory dinosaurs like Allosaurus, and Megalosaurus. Apatosaurus was found in USA and was found by Marsh in 1877. It stood 21-24 meters tall.
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