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Echoes Of Extinction --- not dinos - the end of dinos ...
Echoes Of Extinction
by Staff Writers
Moffett Field CA (SPX) Feb 20, 2009
Paleontologists can still hear the echo of the death knell that drove the
dinosaurs and many other organisms to extinction following an asteroid
collision at the end of the Cretaceous Period 65 million years ago.
The paper culminated a discussion among the authors that had nothing to do
with the end-Cretaceous extinction, said Krug, a Postdoctoral Scholar in
Geophysical Sciences at Chicago. They were following up other work that Krug
had done on the interplay between the geographic range, age and species
composition of modern lineages.
When they compared the data from several provinces, Krug noticed the same
statistical blip in each-a sharp kink in the curve summing up the ages of
living lineages. "When we saw that the kink fell right at 65 million years
ago, we knew we had something," Jablonski said.
Upon further analysis, a significant pattern emerged for origination rates,
an evolutionary signal that had withstood 65 million years of later global
changes in climate, geography and ecology.
"It turned out to be supported in almost all the provinces, and the strength