Positivism & OVEREXTRAPOLATION IN BIOLOGY

[Ken Kinman]

     Although I don't now have time to respond to this thread in any
detail, I think James is making a very important point.  I believe he is
rightly criticizing what I referred to as "overextrapolation" in my
September 1995 article (which reads as follows):
**************SUBJECT (METABIOSYSTEMATICS No. 1): The
September 1995 issue of the Journal of MetaBioSystematics was entitled
"The Misuse of Powerful Analytical Tools in Biology (As It Relates to
the Search for Life's Origins)".
.....Three powerful analytical tools have begun to revolutionize our
ability to solve previously intractable problems in evolutionary
biology: cladistics, molecular systematics, and the computer.
Unfortunately, the misapplication of powerful tools can do a great deal
of damage, and much like a cancer, such damage can spread systematically
and disastrously before we begin to notice the symptoms. Molecular
systematics in particular seems to be generating distressingly myopic
overextrapolation, especially as it pertains to Metabiosystematics
(Kingdom to Family levels).
....Bacteriology in particular could prove to be a worse case scenario
of this type, because it has boldly (I would say rashly) applied these
powerful tools without carefully guarding against the
following pitfalls: false assumptions, cladistic misrooting, circular
reasoning, and failing to realize
just how vulnerable molecular evolution is to the homoplasious
(homoplastic) complexities that challenge even the most astute
evolutionists. I will not here delve into the problems caused by
"unbridled" cladism, but among the positive contributions of cladistics
is its emphasis on careful outgroup selection (i.e., avoiding cladistic
misrooting), although even cladists do not always do this correctly.
 ...The large anagenetic gulf (both phenotypic and genotypic) between
the Metabacteria (= Archaea/Archaebacteria) and Eubacteria gave rise to
the 3-Domain Theory (Woese, Kandler, and Wheelis, 1990; PNAS,
87:4576-4579), in which these two groups of bacteria are treated as
sister groups. Unfortunately, this could be comparable to regarding
reptiles and birds as sister groups. If one made the latter false
assumption, powerful computers and large sets of molecular
and morphological data would no doubt conclude that dinosaurs are the
most primitive reptiles (which is absurd). I believe the conclusion that
togobacteria are the most primitive eubacteria is
probably just as erroneous, resulting from false assumptions, cladistic
misrooting, and perpetuated by circular reasoning. Forcing a probable
derived group (the togobacteria) into the root of the tree
may have distorted it severely. The probably true root (which I believe
to be the Cyanobacteria, although heliobacteria are another interesting
possibility) would appear to be "derived" in such
distorted molecular phylogenies.
...Many reasons for regarding Cyanobacteria as the most
primitive extant cellular organisms (fossil record, Granick
hypothesis/metabolic evidence, properly
analyzed molecular data, etc.) have been explained away in a most
unconvincing manner in many
papers. A less biased reevaluation by all workers involved in bacterial
metasystematics is strongly
recommended. Otherwise the implications could be enormous, both
scientifically and
economically. The uncritical acceptance of the 3-Domain Theory (as if it
was "proven") seems to
be generating false conclusions, not only in biology, but also in
paleontology, chemistry, and other
related disciplines. Therefore, I believe the 3-Domain Theory must be
vigorously challenged and
retested (and hopefully abandoned). Ignoring the problem will only
aggravate the situation and
delay the process of healing and damage control.
....Finally, I must apologize for falling into this
trap myself. Although I separated off Phylum Cyanobacteria as ancestral
to Phylum Eubacteria (in
my 1994 classification of organisms; "The Kinman System: Toward A Stable
Cladisto-Eclectic Classification of Organisms"), I left Class
Togobacteracea as the most primitive of the remaining
eubacteria. I now believe a thermophilic origin of life is very
improbable, and as a former chemist,
I should have realized this earlier. However, although the coding will
require revision, I believe my
formal classification of bacteria remains relatively sound. Traditional
classifications (cladistic or
eclectic) would require extensive revision, but one of the Kinman
System's greatest strengths is its
synergistic ability to be stable, flexible, and more informative
simultaneously.

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