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Re: Cladistics question

In a message dated 98-01-26 18:21:31 EST, nking.ucs@smtp.usi.edu writes:

<< We 
 are not demanding perfection, but rather just to put something objective 
 on the table to argue about. >>

Certain cladists assume a decidedly messianic attitude toward their
methodology, which I find unwarranted and quite objectionable. I also find the
unwillingness of certain cladists to argue their computer-generated hypotheses
with people who do not use cladistics or computers to be equally
objectionable. They seem to forget that the assumption that nature operates
parsimoniously has never been tested (and may not even be testable), and that
at least one recent study has found that almost one computer-generated
cladogram in five does >not< depict a control phylogeny correctly. Nor has it
yet been shown that simply increasing the number of characters in a character
matrix will generate cladograms closer to "the one true cladogram." Cladistics
is perhaps more rigorous than the hit-or-miss systematics we had prior to the
1970s, but it's not at all clear whether it's really >better<, that is, (1)
generates cladograms and phylogenies closer to the truth, and (2) finds and
corrects wrong cladograms and phylogenies faster.

(E.g., segnosaurs are clearly not theropods, but it's going to take almost
forever to convince certain cladists of this...)