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Re: Extinction (was:Religion)



 > If there was a major land plant extinction in North America but
 > nowhere else, that at least suggests that we need to look for
 > a North American cause. Chicxulub fits that criterion nicely,
 > though of course it's possible that something weird happened to
 > North American plant life that was separate from the other K-T
 > extinctions. On the other hand, I'd be very surprised if the
 > Deccan Traps managed to wipe out many plants in North America
 > without having a similar effect in India.
 > 
 > Am I missing something obvious here?
 > 
Not at all.  As I said, I consider the evedence that there *was*
an impact to be fairly substantial.

And it appears to be associated with the Americas.

I just do not think that the impact *by* *itself* caused the
whole suite of extinctions.

What I think happend is that an impact boosted an intermediate
grade (second order) mass extinction into a first order one.

The base intermediate mass extinction was being caused by a
combination of the Deccan volcanism and the major oceanic
regression.

At least that is my current model.  Further data may change it.

[Actually, I even currently lean towards Chicxulub being the
impact site, but I feel unable to state that as more than a bias
until the Late Cretaceous inclusion issue has been resolved].

swf@elsegundoca.ncr.com         sarima@netcom.com

The peace of God be with you.