Once upon a time, around 245 million years ago, dinosaurs roamed the earth. They had free reign over everything. Dinosaurs first evolved from miscellaneous reptiles, and over time became the perfect terrifying creatures everyone knows.

 Some dinosaurs were aquatic, some lived on land. There were approximately 700 different species of dinosaurs, living at the time. Dinosaurs had good lives and had created their perfect environment.

Then 65 million years ago, supposedly an asteroid hit the Earth. This is one of the many theories of how dinosaurs died off. One thing that made scientists believe that this was the reason for the extinction of dinosaurs, was that they discovered limestone rocks all over the world, that dated back to this time.