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Re: No Hedging.



does this mean something like a difference as small as modern domestic
animal variation due to selection?  Like trying to tell the difference
between a Devonian Rex (curly-ratted coated cat) and a Scottish Fold
(curled-over-ear cat) merely by looking at the skeleton (or a Golden Lab
and a Black lab)? So VISUALLY, in person, the mice-and-elephant
creatures could have been distinct from each other but internally they'd
be nearly identical?

Or would they have been even MORE alike than even that and just carried
the new-and-separate genes that would allow for later spciation?

-Betty Cunningham

chris brochu wrote:
> 
> >I respect your opinion--that genetic change doesn't
> >necessarily create morphological change.  But it is just an hypothesis.
> 
> Actually, this isn't entirely my opinion.  I think what people are
> confusing is divergence date and divergence rate.  The lineages today
> including elephants and rodents may have diverged in the Turonian, and they
> may even have been morphologically distinct early in their separate
> histories (though not necessarily recognizably rodent or elephantine).  The
> "burst of radiation" in mammalian diversity during the Paleocene might have
> involved an increase in diversification, but the basic lineages were
> already in place.  Moreover, many of the lineages present in the Paleocene
> are extinct and thus not available for molecular sampling.