[Taxacom] Hanlon's razor (and Portulacaceae)

[Kenneth Kinman]

Dear All,
      When it comes to taxonomy in particular, I think Hanlon's Razor
itself is too simplistic.  Sure, you have a few examples of incompetence
or stupidity at one extreme, and at the other extreme examples of malice
and even conspiracy.  But there is a whole middle ground continuum, and
that is where you will find short-sightedness and complacency causing
problems.                 
       I think mammalogists, ornithologists, and herpetologists are
perhaps more sensitive to the excesses of phylogenetic taxonomy.  That
is where PhyloCode is aiming its initial assault and where its adherents
have already wreaked taxonomic havoc.  I hate seeing that creeping into
the taxonomy of invertebrates and plants.    
       I will be very interested to see how the Portulacaceae-Cactaceae
paraphyly situation is handled.  I can't imagine that they would dump
Cactaceae into a larger Portulaccaceae (that would upset a huge number
of taxonomic end-users).  The temptation will be to oversplit
Portulacaceae into numerous families, and different molecular
phylogenies doing it in different ways.  Will this actually be a case
where taxonomists will finally agree to leave a paraphyletic family
(Portulacaceae) in their classification, and to place something like a
{{Cactaceae}} marker within it to show its phylogenetic placement (the
sister group of Cactaceae might well be a single genus).  Can the urge
to attack every single paraphyletic taxon finally be recognized for what
it has become (a compulsion or even obsession)?         
      The successes of phylogenetic systematics are many, but we should
not short-sightedly ignore the failures and the increasing frequency of
instability.  Neither should we be too complacent about the threat
PhyloCode poses.  It could be successful for dinosaurs, so much so that
the temptation would be there for workers to spread it to other groups
beyond herpetology and mammalogy.    
         --------Ken Kinman