Striking a balance, weighting and Cladistics

[Barry Roth]

This is probably amply discussed in the literature but has never managed to penetrate my thick skull:  why is there a desire to weight characters a priori, unless to influence the outcome of an analysis away from results driven by parsimony?  Under what circumstances is this defensible, except as a form of "what-if" speculation ("What if knee-color were actually the character in our data set that best tracked the historical course of cladogenesis in this group?")

Barry Roth

  "Gabriel A. Eickhoff" <eickhoff at UMICH.EDU> wrote:
Richard and others,
What I'm refering to by "proper cladistics" is post Hennigian phylogenetic
systematics. Mainly, taken from that and as defined and revised by Arnold
Kluge and Steve Farris.

> I wasn't aware that there was such a thing as "proper cladistics." What
> constitutes proper cladistics?

Conceptually, this understanding does not accept weighting by any means. As
I'm sure you know it prefers the more equal opportunity employment of
characteristics without subjective or artifical reasoning behind their
importance...in terms of making a valid evolutionary statments about
phylogeny. Whereas chaps such as Walt Bock at Columbia and Fred Szalay
avidly push for such weighting schemes, contra Hennig 1966.


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