Re: New alvarezsaurid

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

><<Oh well, it looks like another nail in BCF's coffin.>>
>
><I don't see how that's so... BCF says that the lineage from basal
>dinosaurs to modern birds were small, arboreal/scansorial creatures 
that 
>spit off larger terrestrial lineages, right? Alvarezsaurids would just 
>be another one of these lineages.>
>
>And why they could _not_ be the antecendants I don't know, but 
>*Shuvuuia* seems to be the first to have a prokinetic snout, and while 
>this may be novel and still the first appearance of this character that 
>led on to other lineages (Euaves, for example) it still asserts 
>theropods were the ancestors of birds.

     What is Euaves? Anyway some studies done by Buhler and Haubitz 
et.al. indicate that Archaeopteryx may have had a prokinetic skull and a 
streptostylic quadrate. This has been refuted by Elzanowski and 
Wellnhofer in their description of the Archaeopteryx bavarica cranium 
where the quadrate is only single-headed. However, the quadrate does 
show some bird-like characters such as a prominent pterygoid flange, 
which is the orbital process of the ornithurine quadrate. 

MattTroutman

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