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Re: I'm back...



> > - Is it possible that I have found, in the famous illustrations, a
> > synapomorphy for Arctometatarsalia: a rugose crest in the midline on the
> > nasals? Do troodontids have such a thing (ornithomimo- and tyrannosaurs
> do, dromaeosaurs don't, neither do oviraptorosaurs primitively)?
>
> [...] Regarding troodontids, both Byronosaurus and
> Saurornithoides mongoliensis appear to have smooth nasals.  While that of
> Saurornithoides junior looks textured in my bad photocopy, it's not rugose
> in the way tyrannosaurids' are as far as I can tell.

I see. So unless it comes out as an arctometatarsalian synapomorphy,
reversed in troodontids, in a parsimony analysis, I apparently can't use it.

> > - Is it possible that likewise a strongly reduced maxilla and strongly
> > enlarged premaxilla (I'll quantify later :-) , I mean that the biting
force
> > has shifted from maxilla to premaxilla, a prerequisite for prokinesis)
is a
> > synapomorphy for a group that contains only Oviraptorosauria,
Segnosauria,
> > *Avimimus* and Metornithes?
>
> [...] But if you're
> including segnosaurs and such, reversals would abound.

Thanks for ruling out pmx length :-) . I'll maybe look for pmx and mx
height.

> > - I had totally forgotten the drawing of an *Avimimus* skull. Terribly
> > birdlike -- orbit and lower temporal fenestra are confluent, the jugal
has
> > no ascending process. This occurs in Alvarezsauridae (*Mononykus* and
> > *Shuvuuia*) and Ornithothoraces (don't know for *Jibeinia*,
*Longipteryx*
> > and *Protopteryx*, but nowhere else among dinosaurs. May this support
the
> > traditional content of Metornithes and a reversal (due to reinforcing
the
> > skull for ?leaf-eating) in confuciusornithids?
>
> Here's a commonly made error- ornithothoracines do have ascending
processes
> on their jugals, at least until the Ornithurae.  Both the Spanish
> enantiornithine nestling and the basal euornithine Yanornis have an
> ascending process.

Cool news to me. Makes a reversal in Confuciusornithidae a lot easier!

> [...] The fact
> Shuvuuia and Avimimus both have this is one of the characters that makes
me
> think they form a monophyletic group, but I'll wait until all my
characters
> have been verified until I'll officially support it.

Chatterjee supports it in his *Protoavis* paper, I'll write about that
sometime.

> Lack of
> postorbital-jugal contact could indeed support a Metornithes if reversed
in
> Confuciusornis.  Archaeopteryx may also have this character, although it
is
> currently debated.

Bad news: I can nearly tell for sure that the 8th specimen won't resolve
this.

> Ever notice Bambiraptor has only a point contact between
> the bones?  Might be an intermediate condition, or they may not have
touched
> in life, as the skull was disarticulated.

I'll have a look...

> I'm still waiting for your evidence of Late Jurassic
> ornithomimosaur teeth.

Evidence... phew :-] I have read this somewhere in The Complete Dinosaur,
which I loaned several years ago from a library and never saw again.

BTW, thanks to all those who sent me the oviraptorid photos from
dinosaurclass.com. The hallux attaches as far down as in birds and looks
reverted to some degree; the 2nd claw is big doesn't look hyperextendible to
me... which may not say much :-)