Thanks Renfield!
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Posted on 08/05/2012 5:26:49 AM PDT by Renfield
The evolution of new dinosaur species may have surged due to the rise of the Rocky Mountains and the emergence of a prehistoric inner sea in North America, researchers say.
Duck-billed and horned dinosaurs flourished in North America, reaching a peak about 75 million years ago, a time known as the Campanian. For instance, one Campanian region known as the Dinosaur Park formation in what is now Canada saw seven different duck-billed dinosaur species and five horned dinosaur species emerge. A comparable region known as the Hell Creek formation in the United States from the Maastrichtian, the time that led up to the end of the Age of Dinosaurs 65 million years ago, saw only a single duck-billed dinosaur species and maybe three horned dinosaur species at most.
"The reason for this discrepancy in dinosaur diversity has never been adequately explained," said researcher Terry Gates, a vertebrate paleontologist at Ohio University.....
(Excerpt) Read more at livescience.com ...
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