2. Volcano Chain Reaction Theory: Some believe that the large numbers of volcanoes was having the largest chain reaction ever seen. Every single volcano at that time should have become active and then the lava would kill the dinosaur. Conflict: A volcano chain reaction is rather unrealistic. What are the odds of all the volcanoes should become active at one time. Why was the fish and the mammals not killed, a worldwide volcano chain reaction would defiantly kill all species on earth.

3. The Meteor impact Theory: The meteor hit the earth with an incredible speed, and the impact must have been so great that it would have covered the whole planet with dust- and water clouds. The sun could not reach through the clouds, and then the plants did not get their energy and the temperature fell to under the freezing point. Not all animals died at once, the scavengers could still find food to eat, but they could not stand the cold. If the meteor was radioactive then the cold-blooded dinosaurs did not have a chance to survive. Places: In the middle of the eighties they found under an excavation an enormous amount of the element Iridium. This was shocking news for scientist, because they had never found Iridium so close to the surface of the earth. The conclusion became that it was a meteor that had hit the earth and taken the element Iridium with

4. http://library.thinkquest.org/22973/library/dieout.htm