INTRODUCTION-  

Dinosaurs are the best known prehistoric animals. Dinosaurs ruled the earth for more than 160 million years and the last of these prehistoric reptiles died out 65 million years ago. Our pictures of dinosaurs today are of big animals that were more than 25 feet tall. In fact some dinosaur bones that have been found show that there were even dinosaurs as big as dogs. The earth is around 4600 million years old. The first 4 billion years of this is called the Precambrian period. The last 600 million years are called the Phanerozoic. The phanerozoic is split up into three separate eras; the Palaeozoic (ancient life), the Mesozoic (middle life), and the Cenozoic (modern life) eras. In the Palaeozoic era various plants and groups of animals evolved. These included corals, shellfish, insects, fish, amphibians, reptiles, tree-ferns, and conifers. In the Mesozoic era groups typical of modern life arose. These included birds, mammals and flowering plants. Dinosaurs first appeared and then died out in this period. In the Cenozoic era mammals, birds, insects, and flowering plants became widespread. Humans only managed to evolve in the last 2 million years of this era. The Palaeozoic (ancient life), the Mesozoic (middle life), and the Cenozoic (modern life) eras are all divided up into many different periods. In this project we will be looking at the Mesozoic period. This period is divided into three periods; Triassic; Jurassic; and the Cretaceous period which were from 245-65 million years ago. The Triassic period was the first period in which dinosaurs appeared. The Jurassic period is the most famous period in which dinosaurs ruled the earth and the Cretaceous period is the period in which died out and the first modern mammals and snakes appeared.