Theories that explain the disappearance of the dinosaurs The chapter of life that saw the rise of the dinosaurs is one of the most fascinating periods in the history of our earth. It is often the topic that determines children's first approach to science. When these children learn about these intriguing prehistoric beasts, one of their main questions concerns the cause of their annihilation. What could have led to the disappearance of all those creatures, who have lived successfully for millions of years? This question has tormented experts and curious children for decades. In the early 1990s, a “smoking gun” was discovered – supposedly capable of solving the mystery of how dinosaurs met their fate. This discovery was the Chicxulub crater in Yucatan, Mexico. The claim was that this 180 kilometer crater was the impact scar left by an asteroid that collided with the earth. The asteroid was so large and landed with such force that it ended the reign of the dinosaurs on earth. However, recent evidence and research reported in the Proceedings of the National Academy of Sciences suggests that this could not have been the case, because the Chicxulab crater predates the mass extinction by about 300,000 years. Rather, the evidence suggests that two or more impacts caused the mass extinction experienced by the dinosaurs. The fossil record informs us that the mass extinction occurred 65 million years ago. This landmark coincides with and marks the Cretaceous-Tertiary (KT) boundary. There appeared to be relative consensus among scientific professionals that the asteroid impact caused the mass extinction. According to this theory, “debris from the asteroid impact would have superheated the atmosphere so that vegetation would have exploded in......middle of paper......Osaur Impact Theory Challenged. Internet: http://newsvote.bbc.co.uk/mpapps/pagetools/print/news.bbc.co.uk/1/hi/sci/tech/3520837.stmiv[4] Morgan, Jason. The Chicxulub impact predates the KT boundary mass extinction. January 20, 2004. Page 9v[5] Enchanted Learning. Extinction of the dinosaurs. Location of impact crater. Internet: http://www.cooldinos.com/subjects/dinosaurs/extinction/Asteroid.htmlvi[6] Rincon, Paul. Dinosaur impact theory challenged. Internet: http://newsvote.bbc.co.uk/mpapps/pagetools/print/news.bbc.co.uk/1/hi/sci/tech/3520837.stmvii[7] Ibidviii[8] Enchanted Learning. Extinction of the dinosaurs. The KT Extinction.Internet: http://www.cooldinos.com/subjects/dinosaurs/extinction/Asteroid.htmlix[9] Highfield, Roger. The theory of dinosaur extinction: "A myth". The Telegraph – United Kingdom. March 1, 2004. Internet: http://www.rense.com/general49/tho.htm