The Cretaceous Period was the last period of the Mesozoic era. Huge and diverse creatures began to evolve. At the begining, creatures were much like that of the last period, the Jurassic Period. But soon things began to change. Animals, such as the Stegosaurs began to become much more rare. More andvanced species appered. Snakes and turtles really started looking like they look like today. Life was at it's fullest. But around 80 million years ago things started to change. Events like extreme climates and poisoned air by volcanic activity started to deminish the number of species of certain animals including dinosaurs. Then about 65 million years ago, a meteorite the size of Mt. Everest (about 10 km wide) struck the earth. Shortly afterwards, all non-avian dinosaurs vanished, along with pterosaurs, plesiosaurs, moasosaurs, and some reptiles and birds. These events were called the Cretaceous Extiction and ended this period.
Postion in the Timeline Edit
The Cretaceous started 144 million years ago and ended 65 million years ago. Because it is the longest period, it is seperated into two epochs, the Upper and Lower Cretaceous.