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Re: Some thoughts on cladistics [today, on Jerry Springer....]



Ken Kinman (kinman@hotmail.com) wrote:

<Please, give us a break.  Phylogenetic systematics certainly has no exclusive 
patent in using
phylogeny as a standard (far from it), but it seems overly simplistic to use 
phylogeny as the
overriding standard to the exclusion of other views of relationship.>

  But Ken, you use phylogenetic systematics ... I mean, you make assumptions of 
relationships
(phylogeny) and plot them with others to formulate nested groups (to a degree) 
so you are
practicing Nick's proposition.  If I mistook your work, I may be confused....

<It does not always make sense to classify an ancestor with all its descendants 
to the exclusion
of that ancestor's close relatives (especially siblings).  Strict cladism put 
too much weight on
synapomorphies, at the expense of plesiomorphies and anagenetic distance (and 
as imperfect as the
Charlemagne analogy is, it does give one a feel for the problems involved).>

  Pretend I included the analogy with Charles the Great.

  The sibling analogoy works only so long as the group including them is 
capable of interbreeding.
 Siblings are not viable criteria for retention of paraphyletic groups when the 
groups are
completely genetically isolated from one another. Technically, afrotheres and 
xenarthrans are
"siblings" in your usage, yet elephants do not mate with anteaters.  There is 
an intrinsic
exclusivity which is being ignored by trying to use the sibling exception to 
continue to use all
groups as nested paraphyletic groups.  And it certainly fails with ranks 
attached, since they
assume a heirarchy is inherent in evolution.  "Oo, wow, my brother was born 
with six fingers and
toes and an atavistic tail, he must be a new genus...."  That was pure bunk, 
btw, but the gist is
pertinent.

<Cladisto-eclectic centrist approachs to classification (Benton's, for example) 
ARE nested and
based on phylogeny----but they go beyond just nesting and phylogeny, and 
reflect other aspects of
relationship as well>

  Yeah, they use cladistics to formulate the trees and rate character 
acquisition...

=====
Jaime A. Headden

  Interesting Dichotomy:
  "When the state sends someone to the electric chair, it's called murder; when 
the state sends someone to prison, they sanction a gay dungeon."

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