Re: FEATHERED THEROPODS

[smithjb@sas.upenn.edu (Joshua Smith)]

Jeff Poling wrote:
> 
> At 05:25 PM 9/27/98 -0400, Joshua Smith wrote:
> >     Although, let me be a jerk and beat the horse a little bit and 
> >point out that you are using phylogeny and parsimony to gain insight into 
> >the possibility of integument in other groups that are HYPOTHESIZED 
> >relatives.  Just because our cladograms say something is related, doesn't 
> >mean it is.  In support of this, I refer you to the theropod mud-slinging
> >match (oh, I mean "symposium") in Pittsburg in 1995.
> 
>    Just to put it another way, somewhere on my website (I'm too lazy to look
> it up right now) is the point that (paraphrasing from memory) a cladogram is
> a hypothesis of phylogeny.  Neither should they be dismissed as fancy,
> however, as they've supposed (that word put in for the benefit of
> Dinogeorge) to have been formed by a rigorous scientific analysis.
> 
        I am assuming that you are not putting words in my mouth and 
assuming that I am dismissing cladistics outright as fanciful (yes, Tom, 
_I_ just said that).  Being critical of a method (especially one that is 
adopted as a religion before it has paid its dues) is simply a reflection 
of an attempt at being careful.  That is slightly different from assuming 
that the whole thing is complete bullshit (maybe only 70%...grin).

        My problems with the method remain what they have always been:
        the subjectivity of character selection
        the difficulty of cladistics to take intra and intertaxonomic 
morphological variation into account
        the fact that we call cladograms hypotheses but have difficulty 
in testing them with any other mechanism but another cladogram.


-- 
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Josh Smith
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