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Re: Jeholornis prima discussion



----- Original Message -----
From: "Mickey Mortimer" <Mickey_Mortimer111@msn.com>
Sent: Wednesday, July 31, 2002 12:18 AM

> > More derived, certainly, but not more birdlike. Like in *Nomingia*, in
> > birds there are transverse processes even in the pygostyle.

Sorry, Neornithes!

> Both Iberomesornis and Sinornis only
> have four caudals with transverse processes.  They are absent from free
> caudals five and six, as well as any vertebrae incorporated into the
> pygostyle (Sereno, 2000).

Looks like it, judging from the same paper (wow, we can both read :-> ). I'm
not sure there are any on the first caudal, though. There is _something_ on
caudals 6 and 7, but not 5... his figures could still be a little more
3-dimensional... :-) I wonder what the lateral flanges on the pygostyle
are...

> From what I can tell, Confuciusornis has five
> caudals with transverse processes (judging by GMV-2153 and 2131), which
> leaves two free caudals without transverse processes (as seen in
GMV-2132).

>From what Chiappe et al. (1999, fig. 24, GMV-2131) can tell, all 7 free
caudals have well-developed transverse processes. The text mentions "robust
transverse processes" on the "proximal and middle caudals" and "short,
dorsolateral projections (Fig. 25)" on the "last free caudal". I can't tell
whether fused transverse processes are present in the pygostyle, and the
text doesn't, but it looks probable from Fig. 24.

> > -- It's really hard to argue that the last tail vertebra is a pygostyle.
> > [...]
>
> I think it impossible to argue the last caudal is a pygostyle in
Jeholornis.

Looks like it. That's why I listed it under "Problems for me" and wrote
"really hard". :-) I'm not 100 % convinced without a very big photo, but it
would be pretty surprising if this is one while Archie's is not. On the
whole the tail is a lot more Archie-like than I'd expect in anything that's
closer to birds than the dromies are.

> Unless you want to start arguing every coelurosaurs' last vertebra is one.

I'd better not begin that. :-)

> Why would having Jeholornis closer to Rahonavis than avebrevicaudans make
> its lack of a pygostyle any more parsimonious.  The condition in Rahonavis
> is unknown.

Er, that's still my preferred phylogeny: *Rahonavis* closer to Archie and
dromaeosaurs than to avebrevicaudans.

> I think you should just give up trying to call the last caudals
> of Caudipteryx [...] pygostyles, as you have no morphological
> features to justify it and don't doubt the identity of the last vertebrae
of
> other taxa (eg. Archaeopteryx).  You're just trying to fit data to the
> model, like ABSRDists giving Caudipteryx a "quasipygostyle".

I still wouldn't say I have _no_ morphological features to justify that in
*Caudipteryx*. In any case, I'm not a BANDit, I'm capable of abandoning
untenable views (though always very late). I've accepted that tyrannosaurs
are not the sistergroup of compsognathids, that segnosaurs are theropods,
and that Arctometatarsalia only contains ornithomimosaurs. Maybe the
homology of all pygostyles is next :-)

> > -- News to me that Shenzhou means China. I only know Zhongguo ( = middle
> > country). But that's obviously just me, lacking knowledge of Chinese
terms
> > for Chinese history. :-)
>
> It would be sad if true, because it would be redundant with the species
name
> sinensis.  "Chinese snatcher from China".  Yay.

Still better than *Anneavis anneae*, a sandcoliiform in Feduccia's book. --
I thought from the beginning it reminded me of a spacecraft. Fits a lot
better, though somehow it makes fun of the poor birdie. :-)

> > -- Is the hallux of *Shenzhouraptor* really unreversed? [...]
>
> Supposedly.  That's how Altavista translated
> http://www.cas.ac.cn/shownews.asp?id=200207230003 -
> "But in other some characteristics, the Chinese divine land bird actually
> demonstrates the strong primitive color, <snip> the foot çä

= the first.

> è

"Toe" would fit well here, and judging from some figure captions in
Vertebrata PalAsiatica that's what it means.

> liked other
> models the beastly foot class dinosaur such does not have the reverse,
after
> the foot fingernail still to face, indicated its toe does not have " to
> grasps " or " grasps grasps " function."
> And http://english.peopledaily.com.cn/200207/23/eng20020723_100179.shtml
> said-
> "Its first toes have not yet turned inwards like the archaeopteryx ...."
> The hallux looks unreversed to me in the photo,

Interesting.