Re: Fastovsky vs Archibald

[Tim Donovan <uwrk2@yahoo.com>]

--- Phil Bigelow <bigelowp@juno.com wrote:

> Fastovsky is correct in concluding that dinosaur
> diversity WITHIN the
> Hell Creek Formation was not in decline up to the
> K-T boundary.

  It is possible that lambeosaurs became extinct
within Hell Creek time instead of immediately prior to
it. Boyd made a case for the presence of Hypacrosaurus
in the lower Hell Creek but AFAIK there is no evidence
for it in the upper Hell Creek or the lower Scollard,
which is equivalent.
 
 
> That said, some workers have claimed that a Hell
> Creek nodosaur went
> extinct before the K-T boundary.  But considering
> that ankylosaurids are
> generally uncommon in the Hell Creek Formation,
> there is a good
> possibility that the proposed premature nodo
> extinction may in fact be
> only an artefact of sampling/collecting.

  A. magniventris apparently reached the K-T boundary
in WY but Edmontonia might have disappeared over
300,000 years earlier.




                
____________________________________________________ 
Yahoo! Sports 
Rekindle the Rivalries. Sign up for Fantasy Football 
http://football.fantasysports.yahoo.com