What caused the extinction of the dinosaurs?

Gnomon

There have been hundreds of theories as to what caused the extinction. The current favourite is that a large meteorite struck the earth in the region of Yucatan in Mexico/Guatemala, throwing up dust into the atmosphere. The sun's rays were blocked for many years making it very cold. With no sunlight, most plants died. With no plant food, most land creatures including all the dinosaurs and most other creatures died. A few mammals, reptiles and birds survived. Mar 26 02, 8:36 AM

Yaarbiriah

Gnomon may be correct. Geologists have found iridium and stressed quartz and other evidence which suggests such a cataclysm. An alternative theory suggests that the early mammals were the cause of the dinosaurs demise. The earliest mammals were shrew like creatures which lived underground most of the time and were nocturnal so had very few predators. They probably relished the eggs of the dinosaurs and raided them as often as they could. Other theories suggest that climate changes caused food shortages, starvation and fatal migrations. The truth could be any combination of the above and probably other factors. Apr 26 07, 4:50 PM

McGruff

Question #46763. TheAlphaWolf asks: There is a new theory as to why the dinosaurs became extinct - global warming. Why is that? satguru answers: Actually I read yesterday that it was because females died out (not sure why) but maybe they couldn't take the heat as well as males. Maybe not. Apr 23 04, 7:01 PM TheAlphaWolf answers: Not exactly but really close. The females didn't die out but weren't born. Like alligators, crocs and turtles, dinosaurs' sex is determined by the temperature the eggs are incubated in. Since the earth started to warm, only males (apparently warm temps produce males) were born, so without any females, they went extinct. That gives a whole new meaning to stopping global warming doesn't it? Apr 23 04, 7:43 PM Question #65858. 2kool4school asks: How did the dinosaurs really die? pbr-streetgang answers: There are many different theories that claim to answer this question. This site presents some of the more scientifically respected theories: http://www.spaceref.com/news/viewpr.html?pid=15438 May 17 06, 11:11 PM Also see Question #97446 http://www.funtrivia.com/askft/Question97446.html Jul 11 08, 10:00 PM

steele28

It is not known for sure. The possible reason is that man wiped them out, this might soung unlikely and you may think that man has not benn alive then but there have been fossils of man on the "beds" of the Triassic. Man can easily wipe out an animal, like the dodos, Steller's sea cow, and Tasmanian Wolf/Tiger. There are also evidences that the dinosaurs did not die out completely, some may even survive in the Congo Regions and near South American jungles. Aug 21 08, 8:37 PM