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Re: My Phylogeny: Growing Science (and growing e-mails)



David Marjanovic wrote-

> > (Kurzanov, 1987)
> I see. Where have you got that paper from?

A trade with someone.  All in Russian, but with great illustrations.  The
pelvis is shown with dotted lines indicating the pubic foot extended further
posteriorly, the distal ischium and obturator process were more extensive,
and the preacetabular process was expanded.

> > 3. Where did you learn Nomingia, Avimimus, Bambiraptor and
> Sinornithosaurus
> > have ischial symphyses?
>
> Might be typos. I don't actually know :-]

Actually, Kurzanov (1987) shows an ischial symphysis in Avimimus, but I
haven't reexamined the coding of this character yet, so I missed that.

> > I have Archaeopteryx coded as lacking an ischial
> > symphysis (Forster et al., 1998-
>
> True. This is also where I learned that troodontids lack it too.

Hmm.  I'll have to change Archaeopteryx's coding based on Norell and
Makovicky (1997), who say it has a symphysis.  According to them,
Sinornithoides and Saurornithoides have ischial symphysi too, so change that
coding.  I really need to get going on my reevaluation of coding accuracy so
things like this don't happen much :-)

> > why couldn't you have more cranial characters? :-)
>
> Such as? :-9

I have 99 cranial characters, I'm sure you can think of some.

> > 5. There's always "Ginnareemimus", the Thai ornithomimosaur without an
> > arctometatarsus. But I would leave ornithomimosaurs "2" until its
identity
> > is ascertained.
>
> Does it really lack the condition?

According to the illustration in Buffetaut and Suteethorn (1998), yes,
although the proximal portion of mtIII is very narrow.  But as Nick and I
said, it's not certain this specimen is an ornithomimosaur.

> > Bambiraptor is not "sub-arctometatarsalian", it's similar
> > to dromaeosaurids (unpublished, online).
>
> OIC. That makes a difference between it and *Sinornithosaurus* at last --
> save for question marks they are coded the same so far.

Yes, they are very similar.  In fact, I used to advocate them being sister
groups.  Now it seems like Bambiraptor is a basal deinonychosaur, while
Sinornithosaurus is usually a basal avialan.

> > Yandangornis and pygostylians actually have
> > a proximally expanded third metatarsal, more primitive than most
> > maniraptoriformes.  I'm sure Holtz would agree the derived condition of
> > mtIII being ventrally placed in these taxa is unrelated to
> arctometatarsaly,
> > or at least shouldn't be coded as such a priori.
>
> Yet another state? Or another character? *Ornithomimus* has plantarly
placed
> proximal mt III, too.

I don't have it added in my character list yet, but I think you could make a
good case for it being another state.  Of course, you would have a bit of
trouble making the normal-subarcto-arcto-hyperarcto sequence ordered, but
keeping the pygostylian state unordered.  So it might be better to keep it
as a separate character.

> Then *Ornitholestes* (I counted 43 in Glut's Encyclopedia p. 644) comes
in,
> and I have, should I use *Allosaurus* as an outgroup, a synapomorphy of
> Coelurosauria excluding Compsognathidae. Rather uninformative as long as I
> have no outgroup.

There seem to be twenty-seven complete or partial caudal vertebrae known in
Ornitholestes.  Using Osborn's illustration, I get an estimate of 35-40.
Allosaurus is said to have about fifty (Madsen, 1976).

> > It looks like only one vertebra is missing from Yandangornis, so
> > I'd be confident coding it "0".
>
> How can one know that?

Well, I can't really.  Especially as the illustrations in its description
are so poor.  In fact, the illustration shows 25 vertebrae, with three or so
missing in the middle.  I don't trust that illustration at all for this and
other reasons.  The authors say nineteen are preserved, but there were
originally more than twenty.  My guess is that nineteen are preserved
including the very tip, but that a few more are indicated by the break in
the middle.  But who knows.

> I just wrote "According to the same paper troodontids don't have an
> undivided trochanteric crest. Has that turned out to be wrong?". This was
> based on the fact that Forster et al. use this character as a synapomorphy
> of an exclusive (*Rahona[vis]* + Metornithes) clade and not as one of the
> (Troodontidae + Aves) clade. I based the assumption that nothing else has
> that crest on that. Apparently wrong.

Troodon and Iren Debasu specimens (Saurornithoides?) have a trochanteric
crest.

> > and Archaeopteryx?
>
> >From the Forster et al. paper.

Yes, but Tom Holtz (pers. comm. 1999) assured me the preservation makes it
impossible to tell.

> > *copy, paste* I wouldn't
> > code caenagnathids until we know how much of the new skeletons are real.
>
> At least the 1997 paper on *Chirostenotes* doesn't contradict that...

Yes, it seems caenagnathids had short tails.  But just how short is hard to
determine from the few described caudal vertebrae.

> *Achillobator* has "a dorsal fused to the sacrals" or suchlike, and I
wasn't
> sure about, say, *Unenlagia*. (Which I, BTW, didn't code separately, I
> simply trust your assignment of it to Dromaeosaurinae :-) ; according to
an
> SVP abstract *Utahraptor* will fall there too -- we'll know in a week.)

Odd that Achillobator would have that, as no sacrals are known.  Unenlagia
may have come out as a dromaeosaurine in some of my runs, but I don't recall
ever saying it was a dromaeosaurine with any sort of certainty.  Lately it's
been some sort of eumaniraptoran, usually very close to pygostylians.
Wouldn't be surprised to see Utahraptor as a dromaeosaurine, though I think
the traditional dromaeosaurine-velociraptorine dichotomy is overly
simplistic and not representative of the true phylogeny.

> > I would want data from Mesozoic pygostylians before we code them.
>
> Good idea, erm... but as long as there are none, I use living ones.

Which is fine, except that I don't think all neornithines, or even basal
neornithines, have pneumatic caudal vertebrae.  My turkey skeleton doesn't
appear to for instance.

> > Nearly all maniraptoriformes seem to lack nasal ridges, central or
paired.
>
> Not according to PDW. Is that wrong?

Good question.  Greg Paul certainly has much more experience with fossils
than I do.  Compsognathus' nasals are said to be "smooth surfaced" (Ostrom,
1976).  There are no indications of ridges in Dromiceiomimus or Gallimimus,
from their descriptions.  Erlikosaurus has dorsally convex nasals, with a
gentle depression along the midline.  The only ornamentation are some
posterolateral foramina (Clarke, et al., 1994).  From what I can see,
Caudipteryx's nasals seem to be broad and flat.  Crestless oviraptorids
(Conchoraptor, Khaan, etc.) seem to be similar.  The nasals of
Saurornithoides mongoliensis and S. junior look dorsally convex, but I don't
see any indications of paired ridges or tyrannosaur-like median rugosity.
Shuvuuia has flat nasals that appear to have a gentle depression medially.
Deinonychus has a sharp ninety degree angle between the lateral and dorsal
nasal surfaces anteriorly, but this fades posteriorly.  The two nasals meet
in a straight contact (no median depression or ridge) and foramina are
present dorsally (Ostrom, 1969).  Velociraptor has the angled anterior
surfaces and small foramina as well, but there is also a median depression
anteriorly (Barsbold and Osmolska, 1999).  Archaeopteryx looks to have flat
un-ornameted nasals (Eichstatt specimen).

> > 18. "Small pointed" interdental plates is the plesiomorphic condition of
> > having them unfused, so you must reverse the polarity.  I've coded for
> > "interdental plates fused or absent", that being the opposite.
>
> Oh!

I notice in your reply to Jaime, you sate "The *Eotyrannus* paper says *E.*
and troodontids have "small pointed interdental plates"".  Eotyrannus has
fused/absent interdental plates, like troodontids.  I'm not sure if the
"small pointed" morphology is unique to any clade, but tyrannosaurids have
unfused interdental plates.  Interestingly, Stokesosaurus has fused
interdental plates too.  The whole interdental plate issue is complex, with
the difference between fused and absent states obscure and some taxa (eg.
Sinornithosaurus) having both fused and unfused plates.  It certainly needs
more study.

> > oviraptorid furculae are pointed (Barsbold, 1981).
>
> Hmm... they have a hypocleidium but not straight rami that meet at an
angle.

Honestly, I think this character needs more work.  Look at the Allosaurus
furculae in Chure and Madsen (1996).  DINO 11541 looks like Velociraptor's
with an angled apex, but UUVP 6101 looks like tyrannosaurid furculae, with a
rounded apex.

> > Padian et al. (2001) have suggested Caudipteryx's furcula may be broken,
> > which would make it impossible to code.
>
> What is this ref?

Padian, K.; Ji Q.; & Ji S.-a. 2001. Feathered dinosaurs and the origin of
flight. p. 117-135.

> > Basal pygostylians (confuciusornithids,
> > Spanish nestling, Yanornis) have dorsal jugal processes.
>
> I wanted to give Pygostylia a polymorphism, of course, and then forget.
You
> forgot too :-) :

No, I decided to code them as being plesiomorphic.  As confuciusornithids,
enantiornithines and basal euornithines have the primitive state, I feel it
is okay to assume it's primitive for the clade.  Only at the level of
ornithurines do birds start losing the process.

Mickey Mortimer