[Taxacom] Angiosperm origins: Darwin's "abominable" mystery

[Barry Roth]

John,
 
Would it be possible for you to post in one or two paragraphs an abstract of what Dr. Croizat's morphogenetic and biogeographic evidence for that Paleozoic origin was?
 
Thanks for letting me lean on your knowledge of that very dense and voluminous oeuvre.
 
Barry
 
pa,--this is not meant as a fatuous challenge to your statement.  I really am interested in the basis, not least because the origins of high levels of land snail diversity seem to follow on the angiosperm "revolution."

--- On Fri, 3/19/10, John Grehan <jgrehan at sciencebuff.org> wrote:


From: John Grehan <jgrehan at sciencebuff.org>
Subject: Re: [Taxacom] Angiosperm origins: Darwin's "abominable" mystery
To: taxacom at mailman.nhm.ku.edu
Date: Friday, March 19, 2010, 10:12 AM


Well there is nothing much new in this as Croizat presented
biogeographic and morphogenetic evidence for the origin of angiosperms
in the Carboniferous-Permian period. Of course he got ignored by the
dominant botanical authorities. But it's nice to see the 'modern'
technology back him up on that (without acknowledgement I expect).

John Grehan


> -----Original Message-----
> From: taxacom-bounces at mailman.nhm.ku.edu [mailto:taxacom-
> bounces at mailman.nhm.ku.edu] On Behalf Of Kenneth Kinman
> Sent: Thursday, March 18, 2010 11:28 PM
> To: taxacom at mailman.nhm.ku.edu
> Subject: [Taxacom] Angiosperm origins: Darwin's "abominable" mystery
> 
> Dear All,
>       No wonder Charles Darwin regarded the origin of angiosperms as
an
> "abominable mystery".  Even today we are hard pressed to pin it down,
> and the early fossil record before the Cretaceous remains sketchy at
> best.
>        However, new molecular evidence published in Proceedings of the
> National Academy of Sciences earlier this week indicates that even the
> crown clade of angiosperms may have originated as early as the Upper
> Triassic.  This most likely indicates that stem angiosperms (which
went
> extinct) occur earlier.  I don't yet have access to the article, but
you
> can at least read the abstract here:
> 
> http://www.pnas.org/content/early/2010/03/15/1001225107
> 
>        So were the earliest angiosperms just earlier in the Triassic,
or
> back in the Paleozoic as some evidence seems to suggest?   There is
> tantalizing evidence that they may have split off from gymnosperms in
> the Permian or even the late Carboniferous.  There is not only direct
> trace evidence of fossil biomolecules in the Permian, but also
indirect
> genetic evidence (the split between paleo AP3 and PI genes) which date
> angiosperm origins to the Permian or slightly before.  Whether
> gigantopterids (and/or Bennettitales) might be immediate sister groups
> of the angiosperms remains to be seen.  However, both those groups are
> extremely interesting in both their timing and morphology as possible
> gymnosperm sister groups to angiosperms (Phylum Magnoliophyta).
>           -----------Ken Kinman
> 
> 
> _______________________________________________
> 
> Taxacom Mailing List
> Taxacom at mailman.nhm.ku.edu
> http://mailman.nhm.ku.edu/mailman/listinfo/taxacom
> 
> The Taxacom archive going back to 1992 may be searched with either of
> these methods:
> 
> (1) http://taxacom.markmail.org
> 
> Or (2) a Google search specified as:
> site:mailman.nhm.ku.edu/pipermail/taxacom  your search terms here

_______________________________________________

Taxacom Mailing List
Taxacom at mailman.nhm.ku.edu
http://mailman.nhm.ku.edu/mailman/listinfo/taxacom

The Taxacom archive going back to 1992 may be searched with either of these methods:

(1) http://taxacom.markmail.org

Or (2) a Google search specified as:  site:mailman.nhm.ku.edu/pipermail/taxacom  your search terms here