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Restore fully referenced science section
The word '''dinosaur''' was coined in 1841 by Richard Owen<ref>http://www.trueauthority.com/dinosaurs/about.htm</ref>, from the [[Greek]] for "terrible lizard" (fututor). Dinosaurs were a group of large [[reptiles]] that previously lived in abundance on Earth.
The word '''dinosaur''' was coined in 1841 by Richard Owen<ref>http://www.trueauthority.com/dinosaurs/about.htm</ref>, from the [[Greek]] for "terrible lizard" (fututor). Dinosaurs were a group of large [[reptiles]] that previously lived in abundance on Earth.
==Dinosaurs through Science==
What follow are the perspectives on dinosaurs accepted by the vast majority of the scientific community, through use of the [[scientific method]], and taught at the United States' major research universities. Following any of the references in this section will lead to scientific treatment of the issue discussed.
===Extinction===
[[Image:800px-KT_boundary_054.jpg|thumb|right|300px|Badlands near [[Drumheller, Alberta]] where erosion has exposed the KT boundary.]]Close to 65 million years ago, at the end of the [[Cretaceous]] period, and the beginning of what we call the [[Tertiary]] period, an event occurred which has come to be known as the [[K-T Event]]. This event obliterated most life on Earth, plunging the world into something that would now be likened to global nuclear winter, through which few extant species could survive. Although scientists dispute the nature of the K-T Event (selecting among any number of catastrophes that could have caused the significant global cooling that resulted), most find, based on strong geological evidence, that the K-T Event was caused by the collision of a massive asteroid with the Earth, the dust and debris from which shrouded the sky for thousands of years, cooling Earth considerably.<ref>Kevin O Pope, "Meteorite impact and the mass extinction of species at the Cretaceous/Tertiary boundary," Proceedings of the National Academy of Science, available at http://www.pnas.org/cgi/content/full/95/19/11028</ref> The dinosaurs did not survive this cataclysm.<ref>National Geographic, http://news.nationalgeographic.com/news/2002/08/0823_020823_asteroid.html</ref> Evidence of the dust that caused this long winter is still visible, though, as a line of metal of extraterrestrial origin is often visible in sediment worldwide, occurring as a result of the vaporization and then fall of dust from the meteorite's impact, and its compression within the subsequent geological record.<ref>''Ibid.''</ref> The crater is also visible.<ref>National Geographic, http://news.nationalgeographic.com/news/2003/03/0307_030307_impactcrater.html</ref>
===Cambrian Life Explosion===
The extinction of the dinosaurs removed a major food competitor, and predator, of smaller animals. As a result of a new "vacancy" in the food chain, following the [[K-T Event]], vast speciation occurred, as the evolutionary pressure of a new cold age propelled animal species to adapt or die out. What we now know as [[mammals]] were some of the main beneficiaries of this explosion: their fur allowed them to adapt to the cold, and their small size allowed them to conserve energy relative to the huge dinosaurs of the previous age.<ref>Bennet, Shostak, Jakotsky, "Life in the Universe," viewable at http://www.amazon.com/Life-Universe-Jeffrey-Bennett/dp/0805385770</ref>
===Dinosaurs and Birds===
As a number of feathered dinosaur fossils have been discovered, and the similarity in the bone structure between birds and dinosaurs, scientists contend that modern birds are a descendant of dinosaurs. This is cited as an example of [[macroevolution]].<ref>National Geographic, "New Dinosaur Discovered: T-Rex Cousin Had Feathers," http://news.nationalgeographic.com/news/2004/10/1006_041006_feathery_dino.html</ref>
===Dinosaur Speciation===
===Dinosaur Speciation===