Platnick's view of Phylocode
skala at INCOMA.CZ
Tue Mar 12 09:21:16 CST 2002
All questions you are asking were raised and answered in a recent thread on paraphyly. You need not accept the logic of "eclecticists" but you will learn more by reading the mail archives then by asking the same questions again.
To summarize briefly:
From: Thomas Pape [mailto:thomas.pape at NRM.SE]
>But why stress an evolutionary novelty, however 'major' it may seem, by
>lumping groups NOT having this feature into a paraphyletic non-group?
The rationale for eclectic classification (and paraphyletic taxa) is to summarize information on the homologous character states. The logic behind is that (1) homologies are the "same" characters within the evolutionary paradigm and (2) that classification should contain as much character information as possible. Paraphyletic taxa can be more effective in doing so.
>Does the advent of the amniotes in any way justify that non-amniote
>'amphibians' should not have their correct phylogeny mapped in the
Depends on what you mean by "correct phylogeny mapping"; for Ken (and others) paraphyletic taxon is no less "correct mapping" than the holophyletic one.
>Why cannot a 'minor gap' be just as scientifically exciting as a 'major
Minor gaps can receive lower ranking in the system while the major gaps receive higher ranking - quite similarly to the hierarchy of small/large clade hierarchy in the holophyletic system.
>How does a paraphyletic group add to the information content of a
>classification apart from visualising our lack of knowledge?
>Should classifications be scientifically coherent in the sense of being
>logically consistent with the reality of individual taxa (or clades) open to
Evidently, for you clades=taxa; for eclecticists it does not apply. Hence you can hardly ask them to test their taxa for coherence with your own assumptions. Eclectic classifications are - or at least can be - well scientifically coherent, but within the scope of their own theoretical frame. By the way, what do you mean by "critical testing"? I suspect that "testing" in the stict sense is hardly reachable even for the purely cladistic classification.
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