progressive evolution

Phillip Bigelow n8010095 at HENSON.CC.WWU.EDU
Tue Jun 20 14:06:54 EST 1995


Richard Gordon's points regarding the concept of "progressive evolution"
were interesting, and deserve some responses. 
  Richard Gordon wrote:
>1) There is a measure by which organisms can be ranked lower or higher.
                  and...
>2) That evolution more or less continuously produces organisms of even higher
    rank.

  Carl Linnaeus' main purpose for forming a hierarchical 
taxonomic system was, indeed, to place organisms in some form of "divine
ranking" of "lesser" forms and of "greater" forms (the "greater" forms being
closer to god, of course).  The Linnaean system has served us well in the
intervening 240 or so years.  But it should be remembered that Linnaeus'
"rankings" are *now* nothing more than names.  Although some Linnaean names have
higher hierarchical meaning than other names, the general effect of the system
(TODAY) is to put the names in a "nested" hierarchy (like Set-theory of 
mathematics).
As such, Linnaean systematics is hierarchical largely because of construct.
   Cladistics does much the same thing, except it is based on the principles of
evolution and phylogentic theory.  One noticable observation of cladistics
is that all constructed trees have a degree of "polarity"; i.e.,
plesiomorphies lower down the tree vs. apomorphies further up the tree.
  Further, the "fractal-like" nature of phylogenetic trees does appear to 
suggest an over-all increase in "complexity" of the system through time.  
So far, so good...

Now... as to what this all means in terms of *naming* this effect, a problem
arises.  I don't like the subliminal ramifications of calling the
effect "progressive", because it imparts some divine pre-destination, or
some type of religious meaning to evolution.  At best, the term "progressive
evolution" is anthrocentrically-perjurative.  It also implies that life
is progressing toward "something".  Of course, none of these inferrences are
scientifically-supported in any way.  Yet, the term is still used in scientific
journals, and appears to be accepted. 
  It seems preferable to re-name the phenomenon.  We are dealing with a
semantic issue here, not a scientific one.  As a replacement term for
"progressive evolution", why not use the term "temporal-complexity
evolution", since the observed complexity of the phylogeny of any
one tree theoretically increases with time. 
  Evolution theory already has a bad rap in the eyes of the public.  Let's not
give creationists any more ammo by using anthrocentrically-bias terms.
 



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