The world of the Cretaceous Period (65.5–146 million years ago) brought significant changes to life and to Earth itself. The super-continent named Pangaea, begun to break apart during the Triassic, and seaways had begun to invade Pangea during the Jurassic. By the Cretaceous this process was well under way, making Earth’s climate more equable and greatly affecting both plants and animals. This is also the time period of the great extinction.