SPARK July 2014 | Page 14

Dinosaur Timeline In the Mesozoic Era, Earth was a very different place. The world as we know it has seven different continents – Asia, Antarctica, Europe, Africa, North America, South America and Australia. However, when the dinosaurs first existed there was only one super continent, called Pangea. The Earth's crust is made up of different sections, called plates. These plates are constantly moving and continents rest on these plates. This means that as the plates move, the shape of the land is changed. The Mesozoic Era had three periods – the Triassic period, the Jurassic period and the Cretaceous period. s During the Triassic period there wa d the one supercontinent, Pangaea, an a giant ocean, Panthalassa. The Jurassic period saw this supercontinent begin to break up, forming two large continents, Laurasia and Gondwana. period the Cretaceous period, the last Finally, in as we saw dinosaurs, the continents in which we arth looked n them began to form and E know od was ore like it does today. This peri a lot m d lots e were the most dinosaurs, an when ther and lots of different types! 14 | SPARK What Happened to the Dinosaurs? Sixty-five million years ago the dinosaurs died out – there was what we call a 'mass extinction'. Scientists cannot be completely certain what happened, however they think it was most likely that a huge meteorite hit Earth, creating a dust cloud of fumes that shut out the sunlight and changed the climate. They also believe that there was a lot of volcanic activity at the same time, with the clouds of ash and dust from the volcanoes also blocking out the sunlight. These events led to the extinction of the dinosaurs. 15 | SPARK