Re: New alvarezsaurid

["Jaime Headden" <jaemei@hotmail.com>]

<<And if one could prove that alvarezsaurids and oviraptorosaurs had a 
MRCA than with any other dinosaur, my point would be proven. Oviraptors 
don't have to be "birds" per se, to be "protobirds", or derived from the 
same stock, both of which diverged so long ago. This would, 
theoretically, have occured in the Middle Jurassic, with Archie's 
antecendants, and any form thereafter would be "birds". 
Maniraptoriformes, for example, as *Oviraptor*, would be derived from 
the primitive stock that produced Archie on a divergent course, Archie 
bangs his head against a tree, and WHAM has this sudden urge to give us 
all a headache and direct his distant cousins to confuse us mammals on 
avain lineage. Meanwhile, *Oviraptor*, *Shuvuuia*, and *Hesperornis* are 
"birds" and "protobirds".>>

Matt Troutman wrote (being very patient with my insane ideas :) ):

<I still don't understand how you can dismiss all the characteristics 
that alvarezsaurs share with birds because they have a few superficial 
similiarities with oviraptorosaurs. Oviraptorosaurs lack all the avian 
apomorphies which alvarezsaurs have. Yes, oviraptorosaurs are bird- like 
in some aspects ( scapulacoracoid angle, interclavicular angle, 
anteromedial scapular process, dorsal lips on manual unguals, quadrate 
morphology) but most of these are not unique among Maniraptoriformes and 
can be considered either primitive or convergent.>

I'm not dismissing these characters. Only saying they point to a more 
derived state that the oviraptorosaurs, which can be said of all birds 
as opposed to, say, dromaeosaurs, which I actually do believe are 
antecendant to modern birds. Just that the alvarezsaurids are not 
derived from the modern avian lingeage, but I side-course.

<Are you saying that Hesperornis is not a true bird?>

No. He is. I listed him as a "bird" or "protobird". I used quotation 
marks to signify terms were being used; as "theropods" as opposed to the 
new idea of avian theropods, thus the non-avian ones, or "reptiles", 
which are all cold-blooded, as opposed to the new Reptilia, which have 
warm-blooded and gigantothermic members (birds and sea turtles, 
respectively). This is under the precept that my idea, if seen as 
conclusive, or even fairly reasonable, could redefine these two groups, 
or at least shift their descriptions a little.

<There is no eividence that your hypothesis ( however intriguing or 
compelling ) is true. Oviraptorosaurs and Archaeopteryx sharing a common 
ancestor? This is not true because:

1) They lack many avian features that even dromaeosaurs have.
2) Dromaeosaurs share a common ancestor with the stock that spawned 
Archaeopteryx.>

And both *Archeopteryx* and *Dromaeosaurus* shared a common ancestor 
with *Oviraptor,* which was my point. I'm saying that if dromies dropped 
characters that Archie derived from primitive stock (dromies my have 
retained the primitive condition, while Archie derived them from their 
MRCA; or dromies dropped the refined characters that Archie retained, 
again from that MRCA) then those primitive characters would be used as 
*Oviraptor's* starting point, as well as *Shuvuuia*.

This could also mean *Shuuvia* retained the characters, which Ovi's line 
dropped, thus seeming more primitive.

Having the lack of the alvarezsaurian characters which *Shuvuuia* 
carries with Archie, this could mean that they are derived from the same 
stock, with Oviraptorosaurs and dromies the respective outgroups.

unnamed node (in my case, or I don't know what it is)
 \_
  |\_Paraves
  |  |
  |  \__Archaeopterygidae
  |   | \_Aves
  |   |
  |   \_*Dromaeosauridae
  |
  \_unnamed node (in may case)
    |
    \_Alvarezsauria
     \_*Oviraptorosauria

Here, the derived groups (*) are actually the less bird-like 
(comparatively) than the primitive groups, which are very bird like, and 
Aves would have actually sprang from the primitive form, suggesting that 
our famous raptors, "the ancestors of birds", where not so, but were 
advanced protobirds, while birds are actually primitive. From such a 
theme, alvarezsaurids and my oviraptorosauria inclusion would be as such 
suggested. This would also help with the present fossil evidence and 
relative ages for all groups.

unnamed node (in my case, or I don't know what it is)
 \_
  |\_Paraves
  |  |   
  |  \_*Dromaeosauridae
  |    \_Archaeopterygidae
  |      \_Aves
  |
  \_unnamed node (in may case)
    |
    \_*Oviraptorosauria
     \_Alvarezsauria

This would be the cursorial-to-volant form, with each group leading to a 
more "advanced" flying mode, but Archie came before dromies, so this is 
doubtful. Oviraptorosaurs and alvarezsaurids fit in like they did in the 
previous clade, but with less bird-like ovis as preceding the cursorial 
alvarezsaurids, which would actually agree itself with the fossil 
record, rather than the previous clade.

Maniraptoriformes
 \_Maniraptora
 | \_Paraves
 |  |\__Archaeopterygidae
 |  | | \_Aves
 |  | \_*Dromaeosauridae
 |  \_Alvarezsauria
 |
 \_*Oviraptorosauria

This would also agree with the fossil record, and is the presently 
assumed association. This has as much merit as my association, perhaps 
more, but mine simply assumes a closer association of alvarezsaurids 
with ovis than with dromies and Archie. Also, it places ovis outside 
Maniraptora as based on a few avian characters that Ovi lacks, but my 
association argues for a loss of characters from a state that possesed 
so-called "bird" qualities, and thus messed us up. Could this have been 
Archie's wicked little April Fool's prank on us all, or are we really 
stuck with our heads in the grounds. We _really_ need more dino 
specimens, but I guess you all already knew that. :-)


Well, until someone points out another error in my reasoning,

Jaime A. Headden

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