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Re: the P-T boundary



> At 09:06 PM 7/4/97 -0700, Stan wrote:
> >At 05:55 PM 7/4/97 -0400, Ron Dass wrote:
> >>and conifers, once major players, took a back seat to angiosperms.
> >
> >This was well underway *prior* to the K-T extinction.  I have made a
> >considerable study of the Late Maastrictian floras of the US and Canada,
> >and they have a distinctly modern flavor.
> 
> What do you mean "have a distinctly modern flavor"?  I'm not picking a
> fight here, but the Late Cretaceous and Paleocene floras of NA decidely are
> not modern.  Certainly we see many of the families arise then, but at the
> genus level not many have modern day correspondents,
> 
> 
> >And virtually identical floras
> >are known (at least at the generic level) from as late as the Eocene.  I
> >think only a botanist would be able to tell the difference just from
> >walking around in the woods of the latest Cretaceous.
> >
> >In fact the most "unusual" feature of the floras that I can think of is the
> >presence of palms in what are otherwise warm temperate floras. And they are
> >angiosperms.
> 
> Don't be bamboozled by the presence of palms and cycads as an indicator of
> mesothermal climate.  There are a number of extant mid to high altitude
> tropical plants that fit in right at home in cooler, lower altitude
> regions.  This summer, three cycad specimens have been recovered in
> Washington Middle Eocene sites that were greater than 4000 ft elevation at
> time of deposition (based on CLAMP and other analysis).

I wonder if Stan meant that the recent ancesters of our hardwoods 
were already around in the Late Cretaceous, which they were.  It 
might be hard for a non-botanist time traveler to tell the 
difference.

Michael