Fastovsky vs Archibald

[Mike Nathal <mnathal4462@wowway.com>]

In the "Butting Heads" section of the recent Natural History magazine, 
David Fastovsky and David Archibald debate the K/T extinction.

I quote Fastovsky:  " ...every published, quantitative, field-based, 
stratigraphically refined study  addressing this question has concluded 
that dinosaur diversity was unchanged up to the K/T boundary"

and Archibald:     "In the last 10 million years of the Cretaceous, but 
well before the K/T boundary events, the most recent compilations show an 
unequivocal decline in the diversity of dinosaur species."

Hard to see how both of these statements can co-exist.    Unfortunately, 
there was only one reference cited between both articles.