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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).
>
>The most common conifer was _Sequoia_, then occupying niches similar to
>those its close relative, the bald cypress, occupies today.
>

I'd like to discuss this paleobotany area at greater depth with you as time
permits.

Michael
       ---====  Michael Sternberg  ====---
  Amateur Paleontologist and Natural Curiousitarian 
       "I never Metasequoia I didn't like"
            Quod erat inveniendum
Member: Northwest Paleontological Association   
        Vancouver Paleontological Society 
        Botanical Society of America
        Geological Society of America
       ---=============================---     
Pacific Northwest Geology and Paleontology at:  Cascadia - A Paleo Homepage
http://www.cnw.com/~mstern/                          Last Rev date: 11.24.96