Variety Couldn't Save the Dinosaurs |A plot of data on mass
extinctions. Dinosaurs survived the mass extinction that took
place about 200 million years ago. Credit: University of Chicago
When dinosaurs became extinct from the effects of a massive
asteroid hitting Earth 65 million years ago, there were more
varieties of the reptiles living than ever before, according to
a new analysis of global fossil records by a team of researchers
led by a University of Rhode Island paleontologist. "Our
analysis finally lays to rest the old, utterly unsupported idea
that dinosaurs were declining in diversity during the last 10
million years of their time on Earth," said David Fastovsky, URI
professor of geosciences. Fastovsky's analysis, published in the
October issue of Geology, found that early dinosaurs from the
late Triassic period comprised only 40 known genera, but
diversity dramatically increased throughout the time dinosaurs
were on Earth, skyrocketing in the Cretaceous period -- 99 to 65
million years ago -- when a