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



> > > (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.

So it has an obturator process. One less question mark...

> > > 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

Symphyses (or symphysis again, but that's archaic/poetic). That is, in
Latin... it's Greek, and I don't know Greek).

> too, so change that coding.

Strange, strange. I assume they don't say so just in a character matrix? :-)

> > > why couldn't you have more cranial characters? :-)
> >
> > Such as? :-9
>
> I have 99 cranial characters, I'm sure you can think of some.

I lack phantasy here. I can't think of more. I'll add a few dental
characters for sure.

> > > 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 to dromaeosaurids (unpublished, online).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.

Like
+--+--Dromaeosauridae
 |    `--*Bambiraptor*
 `--+--*Sinornithosaurus*
      `--+--*Archaeopteryx*
           `--*Yandangornis* and the rest?

> > > 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.
>
> [...] So it might be better to keep it as a separate character.

Good. I'll add it.

> > > 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.

They don't say the tip is preserved, do they?

> > 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.

I see.

> > *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.

Memory failing. Was that *Velociraptor*? I believe I have read something in
your Details on Achillobator...

> 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.

So should I add it as an OTU? (It's a bit fragmentary...)

> > > 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.

Not all birds have pneumatic tails. This is one reason why I wrote
"occurring" and not "present" :-) ... IMHO it does tell something that it
_never_ occurs in known dromaeosaurs and many other theropods except
carcharodontosaurids (size-related feature, judging from the sauropods which
also have it).

> > > Nearly all maniraptoriformes seem to lack nasal ridges, central or
> paired.
> >
> > Not according to PDW. Is that wrong?
>
> Good question. [...]
> 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 (Eichstätt specimen).

Which is juvenile, and *Archaeopteryx* has dromaeosaur-like ridges and
lacrimal hornlets in both a drawing and the text of PDW.

I'll delete the interdental plate stuff until I have some real knowledge
about that...

> > > 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.

True. (Tyrannosaurid furculae are much deeper, but certain rounded ones --
that of *Beipiaosaurus*, *Protarchaeopteryx*, *Scipionyx* for example -- do
look like that specimen.)

> > > 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.

Which journal? :-)

> > > 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 :-) :

My error.