Re: Caenagnathiformes (toothlessness)

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

David wrote:
> At that time Cracraft thought they were _Neornithes_ because they were 
> toothless. All that is not new in your classification is the very name 
> Caenagnathiformes.>
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    I look at it differently.  In fact this brings up another trend in the 
evolution of coelurosaurs near the origins of Class Aves sensu lato.  
Primitive theropods and primitive coelurosaurs retain the plesiomorphy of 
toothed jaws (not surprising in carnivorous animals).
    However, for whatever reason, there seems to be a relatively sudden 
trend toward smaller teeth (sometimes lots of them) and toothlessness.  It 
happened once in ornithomimes (apparently the largest sister group of Aves 
sensu lato), and perhaps several times independently within Aves sensu lato. 
 Given this trend, I would call these parallelisms, rather than true 
convergences.   Granted this is just a trend, so I didn't mention it earlier 
since there are other much more striking events that probably occurred only 
once (such as ornithoid eggs and the "true" semilunate).
   The trend toward toothlessness is there, nevertheless, and the fact that 
Cracraft thought this applied only to Neornithes is now mostly irrelevant 
three decades later.  **Furthermore**, if Oviraptor's true nature (mother 
bird brooding her nest of eggs) had been known earlier, perhaps Oviraptor 
would have been immediately transferred to Aves, rather than vice versa 
(i.e., Caenagnathus being transferred to dinosaurs).  Oh, how our 
perceptions can adversely affect our classifications.
     I am especially delighted that Caenagnathiformes was named so early, 
and I will henceforth call them caenagnathiforms, rather than that horrible 
misnomer "oviraptorosaurs".  We are apparently stuck with Oviraptoridae at 
family level, but this will hopefully end the creeping of this misnomer into 
the names of more inclusive clades.
         -------- Ken Kinman



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