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Re: titanosaurs



In a message dated 12/4/02 4:26:26 PM EST, qilongia@yahoo.com writes:

<< cladistics
 removes subjectivity of weighting, and in this it offers better insight
 than someone saying "this character is obviously better than that [for no
 reason] and thus is worth _two_ of that character, and should mean that it
 is better...." Eeek, but no. At that point science is out the window. >>

No, cladisitics doesn't remove the subjectivity of weighting, it simply 
imposes the "null" or "equal" weighting on all characters, which is just as 
subjective as any other weighting system. Just as there is no good reason to 
weight one character twice as much as another, there is also no good reason 
to weight them all equally. This is one of those philosophical problems that 
I have with morphological cladistics. At least in molecular cladistics an 
equal weighting scheme is reasonable, since the four bases of DNA have a 
practically even chance of being at any particular locus. In morphological 
cladistics there is no reasonable way to weight characters, so every such 
analysis becomes suspect.