the Extinction of Dinosaurs Our human being has lived on the earth for more than 4 millon years while the dinosaurs had lived on the earth about 200 million years.Compared with the time dinosaurs existed on the earth, the time of human being'existence is quite shorter.However,why did the hyge dinosaurs disappear from the earth? There is a.saying that the earth suddenly became very cold in a time. Since the dinosaurs had not the habit of hibernation, like snakes.and tortoises, to keep themselves away.from cold. not having fur,to protect their body from cold, they.eventually died out.There is another saying that everywhere was dark on the earth when the planets crashed.into the earth and dust hid the sun. a huge number of plants died and the dinosaurs as well as other animals which are feeded on plants gradually died.As the number of animals decreased,the meat-eating dinosaurs were not able to find enough food to eat and they finally died. There are some other sayings,for example,there lived more and more mammals on the earth and they stealed dinosaurs' egg as food,thus causing the gradual disappearce of dinosaurs;the dinosaurs suddenly disappeared because of a strange infectious disease; the drop og global temperature made.dinosaurs'eggs only hatch male dinosaurs...these sayingd in a way seem to have sensebut they are not so convinced!Thetefore, why the dinosaurs'extinction is still a mystery which has not been answered up to now. people now can only imagine how splendid the dinosaurs used to live by information from museum,film and books.