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Re: pink-haired clade (was "going offlist")



> 1   Family Brown-hair
>          Genus Brown 1
>          Genus Brown 2
>          Genus Brown 3
>          {{Family Pink-hair}}
>          Genus Brown 4
> _a_  Family Pink-hair (very prolific)
>          Genus Pink 1
>          Genus Pink 2
>          Genus Pink 3
>          Genus Pink 4
>          Genus Pink 5
[...]
> You could easily convert the above
> into a phylogenetic classification,

If we leave the sibling analogy and treat the above genera as such, I at
least can't make _one_ phylogenetic classification out of this. Is it
--+-- Brown 1
    | -- ...2
    | -- ...3
    | -- ...4
    `-- Pink-hair

or is it

--+-- Brown 1
    `--+-- ...2
         `--+--+-- ...3
              |     `-- Pink-hair
              `-- ...4

or what is it? If I have understood your {{}} markers, you would regard
Pink-hair as sister group to Brown 3, but where shall I place the others?
The Kinman System only traces back sister-group information down to certain
arbitrary levels, except if there is something in the "coding", which I
haven't understood :-( .

[...]
> Unfortunately phylogenies are
> unsettled and controversial (and will be for a long time),

In certain places. Many phylogenetic hypotheses are quite stable and
unchallenged (holophyly of Amniota, Sauropsida, ...).

> and therefore
> these restraints are useful in checking the serious side-effects of purely
> cladistic classifications.  PhyloCode will relax these restraints.

How, in your opinion? I thought you thought it would make everything even
worse ~:-/ ?


> I believe stable phylogenetic information should be encoded in a somewhat
> constrained classification of formal names

Means you (or whoever classifies) decide what is stable and what is not?
When I look at different Linnean classifications, I see just that confusion
that in your opinion phylogenetic taxonomy brings about. I'd prefer some
more objectivity here... and I really think this can be achieved with
cladistics, if one is careful.

> (maintaining usefulness, and
> providing the continuity of tradition whenever possible),

There are several recommendations and notes in the PhyloCode
(www.ohiou.edu/phylocode), which is a long document (er, draft), but IMHO
many people should really read it. It seems that Benton, whose article about
the PhyloCode you mention below, hasn't read some.

>      And as much as cladists hate the idea, a small percentage of formal
> taxa must be paraphyletic (semi-paraphyletic in my system, so the sister
> group information is not lost).  We can quibble how many is optimal, but
> taking it to zero is far too costly.

Well, there MUST be paraphyletic _species_, but species aren't clades,
according to the PhyloCode (Preamble, Preface or somewhere else at the
beginning).

> Mike Keesey has noted that informal
> paraphyletic groups are allowed in the phylogenetic system, but the
> side-effects of pure cladism are too high to justify excluding formal
> paraphyletic groups altogether (and that is where cladists and
eclecticists
> clash most forcefully).  The price is too high and only gets higher with
> time.  Cladists either ignore these "costs" or claim they will go back
down
> in time, but I see it as overexuberant optimism and not realistic (and not
> surprisingly, cladists think the same thing about my approach).

A statement-against-statement situation... :-( As I think I know cladists'
positions on this well enough, could you be more specific, preferably with
some examples? :-)

>      Anyway, as Benton has noted, PhyloCode (and its relative lack of
> constraint) will lead to chaos in nomenclature (that will probably make
> today's mess look like a picnic).  I understand what PhyloCode hopes to
> accomplish, but believe those hopes are built on unstable ground.  Sorry
for
> breaking my New Year's Resolution concerning PhyloCode, but a lot of us
see
> a nomenclatural disaster in the making.
>                   ------Ken Kinman
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