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Re: Diversity after divergence--pre-K/T modern orders.




On Wed, 24 Mar 1999, Thomas R. Holtz, Jr. wrote:

> Okay, to put it another way: eutherian mammals have about the best fossil
> record of any group of terrestrial vertebrates.  However, as we've seen, we
> have a really lousy record of their basal divergence.  If our "best case" is
> this lousy, it is very difficult to see what the pattern (if there is only
> one pattern) truly is.  We can make hypothetical arguments for one
> particular pattern or another, but it is excedingly difficult to test at the
> moment.

I'm surprised that this is true also for more recent strata.  And if
patterns aren't visible, I don't understand how one can develop a model of
expected origination rates.  I'm headed for the references in the Foote et
al paper.  But I'm afraid that because I was abused as a math student,
I'll come away just as ignorant as I arrive!