5 Answers
Why did the dinosaurs die out?
There are dozens of theories to explain a probable cause or causes. Throughout the Mesozoic Era, individual dinosaur species were evolving and becoming extinct for various reasons. The unusually massive extinction at the end of the Cretaceous exterminated the last of the dinosaurs, the flying reptiles, and the large swimming reptiles, as well as many other marine animals. There is now widespread evidence that a meteorite impact was at least the partial cause for this extinction. Impact craters are visible on most planets in our solar system. A spectacular example of this was witnessed in 1994, when Jupiter was struck by a series of cometary fragments. Some of these impact blasts were larger than the Earth's diameter. Other factors such as extensive release of volcanic gases, climatic cooling (with related changes in ocean currents and weather patterns), sea-level change, low reproduction rates, poison gases from a comet, or changes in the Earth's orbit or magnetic field may have contributed to this extinction event.
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12 years ago. Rating: 3 | |
Seems to me that dinosaurs most likely evolved with their food supply…..when there is lots to eat for a long time they get huge and when food gets scarce for a long time their numbers and size goes down. T rex and modern crocodiles may have been related alone those lines, road runners and raptors as well. Going from scales to feathers doesn’t seem like much of a biological-evolutionary leap and considering the time involved has been in the billions of years and that we have been guessing at these “facts” for a couple of hundred years….well I would have to say we are still guessing and making up stories based on a few precious bones found in rocks rather than having a reliable history based on eye witness accounts.
12 years ago. Rating: 3 | |