Re: Being "scientific" about segnosaurs

["Ken Kinman" <kinman@hotmail.com>]

   About 6 or 7 months ago, when I knew a whole lot less about this stuff, 
Mickey Mortimer tested some alternative topologies.  He clearly showed that 
segnosauroids are neotheropods (that was a slam dunk), and I was even 
convinced that they are closely allied with maniraptors.   In my opinion he 
falsified any notion that segnosaurs were non-coelurosaurian or that they 
are polyphyetic.
    However, I've continued to maintain Beipiaosaurus as a separate plesion 
and coded it as sister group to the other segnosaurs (reflecting the 
probably holophyly of this group).  However, the notion that "enigmosaurs" 
are a holophyletic is not nearly as strongly supported, and a paraphyletic 
"enigmosauria" has not been falsified even by Mickey Mortimer.
    Once he finishes his new analysis a month or two down the line, I will 
certainly be paying close attention to those results.  But my prediction is 
that even if the most parsimonious trees still show a holophyletic 
"enigmosauria", that there will also be trees almost as parsimonious with 
segnosaurs splitting off as a separate clade before the caenagnathiform 
clade.  In that case, I would not consider my alternative yet falsified, 
because evolution does not always take the most parsimonious path.
   Anyway, by the time he finishes his analysis, I hope to have more 
characters that support my alternative topology, and I think another 
discussion of these matters would be fruitful at that time.  I trust 
Mickey's analytical approach a great deal, and he may well convince me to 
re-admit the segnosaurs who are now "pounding at the door".  But I will also 
be reviewing Sereno's reasons for excluding them from Maniraptora (I am 
certainly not alone in questioning the holophyly of "enigmosauria").  It 
should be an interesting debate.
        ------  Cheers,   Ken

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