Re: tooth counts in systematics

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

chris brochu wrote:

> What I'm sensing in this thread is the view that "if it's polymorphic,
> then it really can't be used."  Neontologists have been dealing with
> polymorphism for decades - in allozymes, scale counts, segment counts,
> color ranges, even morphometrics.  But they *deal* with it - they don't
> just toss it out.  .  
> 
        I don't think polymorphic traits need to be thrown out--the 
impetus behind this work was to begin accounting for variation in 
characters, not to just look for characters can be simply coded as 
bionomial states.  But as I work with teeth, I started here, and began 
with the stuff that was unambiguous and easy to code first.  A lack of 
rigorous testing of the characters before the analyses are run is the 
whole point as far as I am concerned.



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