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RE: Oryctos Is Back



> It'd be great if these MANIACs who deny a theropod
> ancestry for maniraptorans actually knew theropod anatomy. 
> Of the supposedly avian characters he lists in
> archaeopterygid hands which are supposedly not found in
> theropods...

> - Metacarpal I of Archaeopteryx isn't fused to the rest
> of the metacarpus, which can also be said of all
> non-ornithothoracine birds (Shenzhouraptor, Sapeornis,
> confuciusornithids).
> 
> - Metacarpal I has an extensor flange in Compsognathus,
> Alxasaurus, oviraptorosaurs and paravians (Gishlick, 2002). 
> It gets large in Apsaravis, Yixianornis and similarly
> derived taxa.

> - Metacarpal I was distally ginglymoid in basally all
> theropods (exceptions include derived ornithomimosaurs and
> birds).

> Paul further notes
> confuciusornithids retain flexible digit III, though digit
> II is less flexible in them and microraptorians.


> Paraves
> - metacarpal I reduced to ~30% of metacarpal II length
> 
> Ornithurae sensu Gauthier
> - metacarpals II and III fused to carpometacarpus
> - digit II with reduced hyperflexion
> 
> Ornithothoraces
> - metacarpal I fused to carpometacarpus
> 
> Ornithurae sensu Gauthier and de Queiroz, 2001
> - extensor flange enlarges into process

Bravo!

I note that the above is practically noninformative regarding the part of the 
tree between Archie and every single "bird" lineage on its own. If all the 
BAND/MANIAC effort would be spent on analyses regarding the interrelationships 
of the most primitive members of every "bird" lineage, we might actually get to 
something interesting. 

Because in the absence of a "silver bullet" fossil, we're essentially still 
where Barsbold was at 25 years ago - the presence of "derived avian" traits all 
over a subset of theropods, evolving independently and often several times in 
parallel. Though it must be remembered that Barsbold was extremely ahead of his 
time - his ovoraptorosaurian work put him into a good position to see and 
realize what few other people were prepared to accept back then: that there is 
not a single trait defining a "bird", and that "birdness" is an assemblage of 
homoplasies.

Of course several of these "bird-like" theropod lineages are liable to form a 
clade. But which, and how do they tie together? Are Neornithes closer to 
Enantiornithes than either is to Archie? What did the _Dalianraptor_, 
_Shenzhouraptor_, ... lineages evolve into, if they evolved into anything? Is 
_Rahonavis_ functionally (but not phylogenetically) an Archie redux? Where did 
_Sapeornis_ come from? Essentially, would the real Aves please fly up?

These are the questions that really demand an answer, if we want to get 
anywhere here.


Regards,

Eike

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