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RE: tiny-armed theropods




> On Sat, October 15, 2011 11:51 pm, Anthony Docimo wrote:
>
> It would seem to me that, if the _Troodon_ tooth morphology matches two
> > or more troodontid genera (I assume you meant genera), then you'd know
> > which troodontid clade _Troodon_ belongs to (which, granted, it was
> > probably already grouped in).
>
> If and only if that the two or more taxa who share this morphology share
> it as a synapomorphy, not as a convergence.
 
True.
 
 As soon as I hit Send on that post, I thought "wait, Spinosaur teeth look like 
crocodile teeth."  d'oh.
 
 
> > Is it possible for multiple genera to have identical teeth?
>
> Abso-friggen-lutely.
 
 See above.  my bad.
 
 
> > Even if
> > they're 99% similar, surely that remaining 01% could be used to determine
> > the closest relatives of the _Troodon_ type fossil tooth.
>
> Here is the problem: two individuals of the same ontogenetic status in the
> same population might not have teeth that are 99% identical in the same
> tooth position. The same individual might have teeth in the same tooth
> position but opposite sides that are not 100% mirror images. The same
> individual might have teeth in that position that are not 99% identical
> from one tooth eruption to the next.
>
> Sorry if this messes up people's typological worldviews, but *variation*
> is the great reality.
 
I agree; in hindsight, 99 may have been too high a percentage.