[meteorite-list] Extinction of the dinosaurs in North America"

[Paul H]

GSA TODAY Science Article: 
The extinction of the dinosaurs in North America 
http://www.eurekalert.org/pub_releases/2005-02/gsoa-mga022805.php

Fastovsky, D. E., and Sheehan, P. M., 2005, The
Extinction 
of the Dinosaurs in North America. GSA Today. vol. 15,

no. 3, pp. 4-10. doi: 10.1130/1052-5173

http://www.gsajournals.org/gsaonline/?request=get-abstract&doi=10.1130%2F1052-5173(2005)15%3C4:TEOTDI%3E2.0.CO%3B2

http://www.gsajournals.org/gsaonline/?request=get-document&doi=10.1130%2F1052-5173(2005)15%3C4:TEOTDI%3E2.0.CO%3B2

"Did the dinosaurs really go abruptly extinct 65
million 
years ago at the Cretaceous-Tertiary ("K-T") time 
boundary, or was their K-T extinction the end result 
of a gradual decline over millions of years? The
 imperfect record available from scarce dinosaur 
remains has made this question a true enigma 
and the source of a long-standing and contentious 
debate. David E. Fastovsky and Peter M. Sheehan 
conclude, after a careful review of the fossil record 
from the best-documented dinosaur sites (in 
North America), that the extinction was indeed 
geologically instantaneous. The authors argue 
that the sudden die-off was different in scope 
from previous fluctuations in dinosaur diversity 
through the dinosaurs' 160 million years on Earth. 
The authors consider the dinosaurs to have been 
direct casualties of the K-T impact of an asteroid 
with Earth and review several potential explanations 
for the mechanism of the extinction. All of these are 
concordant with the asteroid impact as the ultimate 
cause."


	
		
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