NT & modern cladistics

Ken Kinman kinman at HOTMAIL.COM
Tue Apr 22 03:31:16 CDT 2003

I agree with Don,
     Too much hubris.  Couple that with the rigidity of "cladifications"
(Mayr's term for strictly cladistic classifications), and you end up the
typical American "throw away" classification.  One hypothesis and its
corresponding classification becomes obsolete, so throw it away and propose
a new one-----sometimes over and over and over again.  The acceptance of any
single cladification is often ignorance at best, and even stupidity at
     That is PRECISELY why I opted for coded classifications that can slowly
evolve with new information and interpretations.  They are slowly modified,
rather than the revolutionary overthrow of one cladification over another in
succession.  Such instability inevitability leads to an eroding confidence
in systematics as a discipline.
      A single ordered classification can be modified (recoded) to reflect a
number of different hypothetical phylogenies.  And furthermore, a simple
reordering of the taxa (coupled with such recoding) can greatly multiply the
number of possible hypotheses that can be reflected with the same taxa.
This is the only way to achieve long-term stability of classification.  Had
Hennig had broad experience classifying taxa above ordinal level, I think he
would have come to understand the limitations of cladifications and that
what might work reasonably well for flies would inevitably lead to
absurdities when applied to higher taxa.
      And ultimately this leads to the even bigger question of paraphyletic
taxa, which I truly believe should be the exception (not the rule).  That
they should be minimized (in as far as possible) has always been clear to
me.  But that they should be forbidden (and declared unnatural) is something
future generations of biologists will find hard to understand and will even
made be the butt of jokes.
      Today's intuition (be it that of an eclecticist or a strict cladist)
is most likely to break down when it comes to basal groups where our
understanding and hypotheses are the weakest.  Those are the areas where I
choose to erect paraphyletic groups.  And I now VERY much regret not having
done this with basal angiosperms in my 1994 classification.  A return to a
broad paraphyletic Magnoliales (which I proposed here on Taxacom last year),
slightly modified from the Magnoliales proposed by Thorne, will clearly
stabilize angiosperm classification.
     Even I can sometimes be tempted by the hubris of excessive
cladification, but I'm not afraid to admit it.  But on the other hand, we
cannot use paraphyletic groups as a crutch either, and strict cladification
clearly arose as a reaction to the opposite extreme of unencumbered
paraphyly.  It is high time we strike a balance between such extremes, and
limited paraphyly coupled with some form of coding seems inevitable to me.
     The disunity (a virtual civil war) of systematics has left us
vulnerable to the kinds of recent cuts in funding for systematics overall
(and squabbling over a relatively shrinking pie).  Only with a unified
approach will we be unified enough to stop the shrinking of such funding,
and molecular biology will inevitably also suffer a slow decline if it
chokes off the morphological base upon which it ultimately depends.  A house
will crumble without a solid foundation.
                ---- Ken Kinman

>From: Don.Colless at CSIRO.AU
>Reply-To: Don.Colless at CSIRO.AU
>Subject: Re: NT & modern cladistics
>Date: Mon, 21 Apr 2003 14:43:01 +1000
>Chris Thompson has it dead right; and despite rumours to the contrary, I
>have never opposed the reconstruction of phylogenies - only the hubris
>that often attends the process. And the insistence that classification
>should be based on a one-to-one mapping on the hierarchy displayed in
>some phylogeny.
>After years wondering just how one could really accept any one such
>reconstruction, I now believe that a process like Hennig's (as described
>by Chris) is about right. As in all science we have to base conclusions
>(which are always hypotheses and to some degree tentative) on a set of
>"basic facts". And that set can only be chosen by a process that is
>largely informed by judicious, well-trained intuition. Our current
>problem is, that we don't yet (or no longer) have a "college" of wise
>men to judge those intuitions.
>There is a current fashion to refer to phylogenies as "hypotheses"
>(simpliciter), without any reference to the (even qualitative)
>credibility that must attach to an hypothesis if it is to be of any use.
>This is nonsense, and evading the basic responsibility.
>I should, I suppose, admit to being a dipterist, once an amiable
>correspondent with Willi Hennig, and a good friend of Lars Brundin.
>       Don Colless
>       CSIRO Div of Entomology,
>       GPO Box 2600, Canberra, ACT, 2601,
>       Tel: 02-62464270,
>       Email: don.colless at csiro.au
>       Tuz li munz est miens envirun
> > -----Original Message-----
> > From: christian thompson [mailto:cthompson at SEL.BARC.USDA.GOV]
> > Sent: Thursday, 17 April 2003 12:35 AM
> > Subject: NT & modern cladistics
> >
> >
> > Dick, Don, et alia, are right when they say, to quote Dick:
> >
> > "Despite wishes to the contrary, modern cladistics is
> > an outgrowth of NT."
> >
> > Everyone one should know that Steve Farris started off in the
> > NT group and only later switch over the emerging American
> > Museum school of "cladisitcs," etc.  And thus was born
> > "phenetic cladistics."
> >
> > What has really been lost today is what Willi Hennig was
> > really all about. As working dipterist, I can tell you what
> > Hennig really did was produce "Argumentation Schemes," not
> > cladograms, etc. There was nothing about "modern cladistics"
> > where you take the "total evidence," following parsimony, run
> > everything thru a computer and produce the best answer, which
> > for insects and their allies as published in Nature last year
> > showed that Hennig's flies where the sister-group to
> > barnacles! [Darwin's group!]
> >
> > Hennig studied diverse "character systems," such as wing
> > venation, immature stages, male genitalia, etc., and look at
> > a broad range of exemplars, including fossils, as well as
> > looking at distribution
> > (geographic) patterns. From all these sources of information
> > he developed his hypotheses, basing them on character
> > evidence as he saw it. Yes, selective character evidence. If
> > some molecular sequences put Drosophila with the barnacles,
> > he would have ignored them.
> >
> > Fortunately Willi Hennig died young and, thus, unlike Ernst
> > Mayr, did not have to suffer to see his Science and Name corrupted.
> >
> > Oh, well ...
> >
> >
> >
> >
> >
> > F. Christian Thompson
> > Systematic Entomology Lab., USDA
> > c/o Smithsonian Institution
> > MRC-0169 NHB
> > PO Box 37012
> > Washington, DC 20013-7012
> > (202) 382-1800 voice
> > (202) 786-9422 FAX
> > cthompso at sel.barc.usda.gov e-mail
> > www.diptera.org  web site
> >

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