Dailly assignment : The Extinction of the Dinosaurs

Topic : The Extinction of the Dinosaurs

For almost 100 million years, dinosaurs and other large reptiles ruled the land, sky, and
the sea. Dinosaurs may come in large sizes and shapes. According to scientific researches, approximately 65 million years ago, these huge reptiles died out and mammals took over the earth. Over the years scientists have developed many theories to explain the cause of the disappearance of the dinosaurs and the other large reptiles. Three causes can explain their disappearance: the earth's climate, the disease, and the earth's collision with a large asteroid. Some scientists believe that the number of dinosaurs reduced and event disappeared due to the a change of the earth's temperature. The earth first got tropical climate and at the end of Cretaceous period, the temperature dropped and the climate became much colder. For this reason, most animals died. The cold temperature may have cause ed serious problems to the dinosaurs. Since those huge animals didn't have feathers to protect themselves against cold, they couldn't adapt to the new climate. Scientists lead another reasons of the extinction of the dinosaurs to many diseases. They think that diseases killed the dinosaurs when large groups migrated across land bridges between the separate continents and infected one another with new illness. Other scientists lead the disappearance of dinosaurs to the asteroid theory. In the late 1970s, scientists discovered evidence for the abrupt end to the age of dinosaurs. They suggested that about 65 million years ago, the earth was struck by the a huge asteroid. The asteroid once destroyed in explosion, billions of tons sprayed up into the air . A thick cloud of dust blocked out sunlight for a long time. Consequently, plants unable to make food died. The lack of plants killed many plant-eating dinosaurs.

Written by David Lateu