[Taxacom] LOL (was Re: New lizard species)

[Kenneth Kinman]

Hi Curtis,
      Not exactly.  To be more precise, a paraphyletic "grade" or stem
group is a series of plesions, splitting off in succession.  A single
plesion is actually a clade (see any of my classifications which include
plesions).     
       As for mixing holophyletic and paraphyletic taxa (clades and
grades) in a classification, it hardly overloads well-constructed
classifications.  Instead it can make them more balanced, informative,
and utilitarian, at least if one is doing it properly.  What overloads
most classifications these days is too many intermediate taxa, because
strict cladists want to name almost every clade ad nauseum.  Grouping
series of plesions into a paraphyletic taxon can often actually avoid
the overly-cladistic overloading of classifications.  
       -------Ken Kinman
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Curtis Clark wrote:
On 6/10/2010 12:03 PM, Jason Mate wrote: 
> Although I disagree with (but respect) most of Richard´s >comments I
must say that strict adherence to monophyly is a >potential headache:
beautifully logical but a practical >mess. Stem groups do serve a
purpose, if nothing more than >a convenient bric-a-brac box, in
particular in >paleontology. 
     Those used to be called "plesions". There's >nothing wrong with
grades as taxa (in fact, one might >imagine, or at least I might
imagine, a classification made >entirely of grades). But mixing grades
and clades is, to >use computer science terminology, overloading the
>classification.