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Re: The Papers That Ate Cincinnati



> On 5/5/07, evelyn sobielski <koreke77@yahoo.de>
> wrote:
> >
> > In a nutshell, if monophyly as
> > understood by Hennig rather sooner than later
> turns
> > out to be an exception rather than the rule, I'll
> be
> > the last to be surprised.
> 
> I'm not clear on what you mean by this. The
> exception in terms of
> what? Monophyletic entities do exist....

The point is rather than non-monophyletic descent
*also* exists, and not actually little of it.

 (T) (A)
 |_|_|
 |   |
  \ /
   |

This is a crude representation of the internal pattern
of the _Triticum_-_Aegilops_ clade. What would
PhyloCode do with it?
This is not an uncommon phylogeny in plants. Branches
have varying widths; usually the hybrid branch is
small but not necessarily so. It also occurs in
animals (Anas, Cnemidophorus, IIRC some Osteichthyes,
Rana... possibly common as crap in invertebrates,
possibly just frequent & widespread).

Then, lichen. May or may not have a single basal node.
This node or nodes unites 2 lineages of descent from
entirely different clades into a new organism.

Then, anything that is unicellular and reproduces
clonally. In these cases, ontogenetic genetic changes
(eg by HGT) *are* possible phylogenetic changes. How
to define clades in these?

Or try Woese
(http://www.pnas.org/cgi/reprint/97/15/8392 and
http://mmbr.asm.org/cgi/reprint/68/2/173).

The point seems not that phylogenies are unfeasible as
a classification framework; they better should be
useful and they are. It's rather that there is a
trade-off between rigidity of the classification
system and appropriate representation of evolutionary
reality. It's a bit like the Classis problem, only the
other way around.


(If you like to lose respect in Mayr,
http://www.pnas.org/cgi/reprint/95/17/9720.pdf for his
critique of Woese's "Henningian" decision to recognize
the distinctness of the Archaea. Bleh. He should have
stuck to the BoPs.


                
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