Passage: About 200 million years ago, much of the earth was very warm and wet all year. This heat and wet air caused thick plants and tall trees to cover the land and make jungles where many animals began to appear. Dinosaurs were the first group of animals to appear on the earth 140 million years ago. Some dinosaurs were as tall as a three-storey building. Others were as small as cats. Studying fossils gives us facts about dinosaurs. For example, the shape of a dinosaur’s teeth gives us information about whether it ate meat or plants. Why did dinosaurs disappear from the earth? Many people believe that it was because of the change in the earth’s weather. What caused the jungles to appear?