Ernst Mayr and "Life"

[Ken Kinman]

Dear Taxacomers:
    I received a letter from Ernst Mayr this past week, and even at 95, he
seems to be going strong, and still publishing and getting more awards.  I
think it's wonderful that he still writes letters in longhand.  E-mail seems
to make even typed letters (by snail mail) increasing unusual, but written
letters (especially among scientists) are getting pretty rare.
     The main reason I am writing is something I saw on a Berkeley site.
I'm sure it would make Ernst grimace---it certainly made me cringe.
     The overall classification of life at this site (see URL below), shows
the now popular three domains, but in circular fashion with no root.  This
didn't bother me too much until I saw the following statement:
  "No one of these groups is ancestral to the others."    Sounds like
someone still believes in the Ur-eukaryote, and although I don't think Woese
believes in his three Urkingdoms any more, he certainly didn't make that
clear in his paper (Sept. 1998) in Proc. Natl. Acad. Sciences (in his weak
response to Mayr's article of the month before).
      The gap between Eubacteria and Archaebacteria is closing fast as more
rRNAs (and other genes) are sequenced.  But even before that became
apparent, it was always clear to me that three domains of rRNAs should not
be translated into three domains of life.  The prokaryote-eukaryote
distinction is far more fundamental, and the Three Domains completely
trivialize over 2 billion years of eukaryotic evolution.  This is true
whether or not you buy my theory:  that Archaebacteria (Metabacteria) are a
relatively derived branch of Eubacteria, with Eubacteria arising about 3.9
billion years ago, and the misnamed Archaebacteria arising about 3.0 billion
years ago (and the Eukaryotes arising from a merger about 2.5-2.8 billion
years ago).
     But what worries me the most (and I seem to be still alone in warning
scientists of this) is the continued use of "Archaebacteria" (a probable
ingroup) as an outgroup to Eubacteria (which is like using birds as an
outgroup the reptiles, which would force dinosaurs to the base of an
absurdly skewed reptilian tree).  All this may sound arcane and even trivial
to many, but the one important thing that Woese and Mayr agreed upon (in
their PNAS debate last year) is that these matters will have an extremely
important impact on the future of science (and biology impacts all the
sciences).
     It could even impact expensive NASA projects if they put too much stock
in the thermophilic origin of life on Earth (another important facet of
Woese's paradigm, which appears to be supported only by badly skewed
phylogenies). Anyway, here is the URL for that Berkeley page that has gotten
me somewhat stirred up:
http://www.ucmp.berkeley.edu/alllife/threedomains.html
                      Sincerely, Ken Kinman

______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com