[Taxacom] PhyloCode battles itself

Kenneth Kinman kennethkinman at webtv.net
Sun Sep 19 23:17:00 CDT 2010


Dear All,
       I was reading a new paper on the phylogeny of maniraptoran
dinosaurs today, and it brought to mind again the "legalistic" problems
that PhyloCode will generate.         
      In particular, there is the issue of pseudo-clade
Arctometatarsalia (which I have been criticizing for many years), and as
it turned out, it is not a clade at all (even the original author of the
clade name admits it was based on a homoplastic characteristic of
certain foot bones that evolved convergently for running).   Trouble is
that Holtz, who proposed the clade in 1994 based on this homoplastic
characteristic, then later refined it to include just a single
restricted clade that possesses that characteristic, thus considerably
restricting its composition.           
      Sereno (another PhyloCoder) objected to such a drastic change in
phylogenetic definition (rightly so in my opinion), and proposed instead
the clade name Ornithomimiformes, which makes a lot more sense for this
restricted grouping.  This presents a dilemma to the PhyloCoders as they
supposedly approach the time that they actually formally initiate
Phylocode and issue their first formal list of PhyloCode names and
definitions.  Hopefully they will go with Ornithomimiformes even though
the unfortunately altered (restricted) definition of Arctometatarsalia
was proposed earlier (although later than the clearly original
definition of the taxon which turned out to be polyphyletic).     
         This is just a taste of the kind of legalistic wrangling I see
PhyloCode generating, with PhyloCode "lawyers" arguing against ofher
PhyloCode "lawyers" which is the more appropriate name.  It sort of
reminds me of those conventional biologists (in the 20th Century) who
argued over strict priority (no matter how old and forgotten the name)
and those advocating the 50-year (or the more recent 100-year) rules,
The only big difference is that the original definition of
Arctometatarsalia was clearly polyphyletic, but was (no doubt
inappropriately) redefined as a new restricted clade when it turned out
to be polyphyletic (even the author Holtz now admits the original
definition defined a polyphyletic group). Such non-forgotten names
originally defining an unnatural polyphyletic group (such as
Arctometatarsalia) are even worse than long forgotten names that are
mere synonyms (of natural groupings).    
      Stay tuned for even more more absurdities when PhyloCode actually
becomes official.  Not only such legalistic battles between PhyloCoders
themselves, but other battles, such as where they have inappropriately
redefined  paraphyletic groups with restricted clade defintions
(especially for Classes Amphibia and Reptilia, or even Domain Bacteria),
The mess now unfolding in dinosaurs (the epicenter of PhyloCode
activity) will spread to many other taxa.  See the link below for a
minor preview of things to come, even as PhyloCodists are already
battling amongst themselves about their favorite groups (dinosaurs,
which they insist must include Class Aves, simply because the latter
render Class Reptilia paraphyletic).  I submit that such paraphyly is
FAR more useful and stabilizing than any definition of Arctometatarsalia
(which could soon be permanently redefined even that definition is
rejected by other prominent PhyloCodists).   Even after over 10 years of
delays, the implementation of PhyloCode is probably not a good idea, and
perhaps never will be.  They are already acting more like the U.S.
Congress with its disfunctional infighting.  I'll take the minor
wrangling within the ICZN any day to the legalistic crap the PhyloCode
will probably generate.                                      
           ---------Ken Kinman          

http://en.wikipedia.org/wiki/Ornithomimiformes





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