Striking a balance, weighting and Cladistics

[Gabriel A. Eickhoff]

In response to Curtis, which I can only take his "[...]" response as an
understandable lack of understanding of my own vague statement.

>At 10:19 PM 2/14/01, Gabriel A. Eickhoff wrote:
>>   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.

On Wed, 14 Feb 2001 22:47:46 -0800, Curtis Clark <jcclark at CSUPOMONA.EDU>
wrote:

>
>[...]

  Their 1969 work "Quantitative phyletics and the evolution of anurans.",
and nearly everything after, especially on Kluge's part. Anyway, its not
really that important. Ok. "proper cladistics" was obviously an over
simplification for you. Shall we move on from that? What I'm after is
discussing the validity of weighting in cladistics. What do you say? Yes,
No? Why? It is felt by several people that weighting has no place in
"modern" cladistics. Bock, Szalay, Kluge, even though the first two advocate
it, but in an "Evolutionary Systematics" way. See Szalay 1967 in
"Evolutionary Biology" vol. 18, ed. Max K. Hecht, Bruce Wallace, and
Ghillean T. Prance. Or perhaps Bock 1981 in American Zoologist. Or Szalay
again in the same text. While your at it, check out Cracraft, which is the
article between the other two. Its clear that they feel there is a clear cut
distinction between the two "schools" ie. evol. syst. and cladistics. This
is what I refer to as "proper cladistics", simply to distinguish it from
evo. syst. if you had/or did read my first post of this topic, you would see
that.
  Simply what I'd like is to get some good conversation on this subject so
ideas can be trown around and worked out, and in cases like mine, simply
clarified...thats all. Sound fair enough? Hope so. Lets start again.

  Emerson and Hastings 1998 in The Quarterly Review of Biology stated:
   "There is a perceived difficulty in testing rigourously the causes of
morphological character covariation (Kluge 1989) and, as a result, these
characters are generally treated as being independent. All characters are
given equal weiight under the assumption of character independence. This, in
iteself, is a character weighting scheme (Wheeler 1986), one that is not
necessarily grounded inthe biological reality."

  Now, at first glance, I have to say that that argument doens't hold much
water. At the same time, i'm compelled to reason with it because I can see
how independence would be a form of weighting. A analogy for this could be
made by saying, having no light on an object is just another way of seeing
it...just without light. Assigning no weighting scheme, is just another way
to give characters weight, just without "relative" weight.


-Gabe