Re: New alvarezsaurid

["Matthew Troutman" <m_troutman@hotmail.com>]

>That's my point. All theories suggest convergence to one great degree 
or 
>another. Archaeopteryx/Dromaeosaurus are a natural group, with 
cursorial 
>dromies and devilish volant archaeopterygians either deriving from a 
>MRCA than Oviraptorosaurs (I never doubted this).

     There would be less convergence if alvarezsaurs were regulated to a 
position in Aves that is above that of Archaeopteryx and even at a 
sister-relationship with ornithurines. 

>All our conversation about Aves convergence shows that birds are very 
>likely to produce or drop characters (some diagnostic of birds). It is 
>true that all birds can be reasonably assumed to be as derived from 
>Archie or Archie-like stock. But there is no present ancestor closer to 
>alvarezsaurids and mononykines or whatever than to oviraptorosaurs to 
>either refute or acclaim my "evidence". I believe we are on as even a 
>keel as BCF and BADD or BAMM are, and thus either of our views are as 
>prevalent as others, perhaps more so.

     In Aves there is a LOT of convergence, but what this convergence is 
is convergence where you can still trace the direct ancestors or 
sister-groups using many methods. But, to my knowledge, few groups have 
lost the diagnostic features of Aves, they just modified them. Now, if 
oviraptorosaurs are related to the dromaeosaur/avian clade the supposed 
lost characters would appear in a modified form. 

>Not to sound rude, but I do find it seemingly unreasonable of you to 
see 
>that I have a point, but you are very correct. There is a lot of 
>parallel in *Shuvuuia* and *Oviraptor*, even possibly coeval, but I do 
>not think it is coincidence. <shrug>

    Sorry I made you feel that way, I guess I can seem sort of abrasive 
at times. 

>Give me a rebuttal theory of alvarezsaurid evolution, and I'll reflect 
>your points.


     A model of alvarezsaur evolution with view convergences would be if 
they were birds that were above Archaeopteryx. All of the avian 
characters can be explained. The characters that are shared with 
oviraptorosaurs can be considered as convergences related to the 
flightness nature of alvarezsaurs and the strange, unknown habits of 
oviraptorosaurs. 


MattTroutman


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