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Re: Coelurosaur Analysis Update for Dilong
David Marjanovic wrote-
> It's indeed objective, and the weighting is a good idea. But it's probably
> not a good idea to have the same number of states for every quantitative
> character! For some characters this could result in huge cases of
> polymorphism due to individual variation -- like, every species that has
> state 2 also has state 3, and perhaps vice versa.
What's the problem with this? Polymorphies are easily codable. As long as
they're weighted equally, polymorphies of such quality should make little
> > - Adding that new enantiornithine from CJES
> Wwwww...which one is that?
This one http://dml.cmnh.org/2004Sep/msg00219.html .
> > `--+--+--"Alashansaurus"
> > | |--Fukuiraptor
> > | `--+--Megaraptor
> > | `--"Tanycolagreus"
> Hey cool. :-)
Yeah, though my Megaraptor OTU only includes Novas' and Lamanna's specimens,
> > |--Iliosuchus
> > |--Stokesosaurus
> So dissimilar from *Aviatyrannis*?
Stokesosaurus has a more anteriorly oriented pubic peduncle, a better
developed supracetabular crest and more poorly developed antitrochanter.
Iliosuchus seems polymorphic for the second character, and resembles
Stokesosaurus in the first.
> > |--+--Coelurus
> > | `--Therizinosaurus
> Ouch. Must be an artifact of the half-done coding...
> > `--+--+--Erliansaurus
> > | `--+--Nothronychus
> > | `--+--Alxasaurus
> > | `--+--+--Beipiaosaurus
> > | | `--Neimongosaurus
> > | `--+--Segnosaurus
> > | `--+--Erlikosaurus
> > | `--Nanshiungosaurus
> Interesting that *B.* is so high up.
This is supported by-
more derived than Erliansaurus
- manual ungual I smaller compared to II.
more derived than Alxasaurus
- groove demarcating medial tuber of humerus.
- pubic peduncle more anteriorly oriented.
- short postacetabular process.
- cuppedicus fossa absent from ilium.
- post-trochanteric process (on postacetabular process tip) absent.
Xu et al. placed Beipiaosaurus basally based on- large skull size; shallow
humeral flexor groove; slender metacarpal III; round ischial shaft section;
high tibiofemoral ratio; metatarsal I does not reach tarsus. I quantify my
metacarpal III slenderness character, and cannot determine its width from
the figures, so could not code Beipiaosaurus. My skull size character needs
decoupling from neck length. The others haven't been included yet.
> How did you code *Graciliraptor*? The day I got the latest JVP,
> *G.* paper was finally available, and it has turned out to be rather
> disappointing. There's no illustration of the entire fossil, and the paper
> is rather short.
What's illustrated is basically the entire fossil (I have a photo of the
latter). True, it's mostly limbs, but I got 36 characters coded from it.
> Man! Why haven't I got that idea much, much earlier -- that *Yandangornis*
> and *Avimimus* could be closely related! What do they share in your
> A big toothless pmx? Extra-long legs?
The toothless premaxilla is it. The Omnivoropteryx node below is formed
from a character shared by Omn and Avi, and another shared by Omn and Yand
(both unknown in the remaining member of the clade). I really need those
pelvic characters coded to shove Avimimus away from birds.
> Interesting that *Jixiangornis* is so far away from the...
> phenetically... almost identical *Shenzhouraptor*.
They differ in 9 codings in my matrix.
> Good to see how far apart *Omnivoropteryx* and *Sapeornis* can end
> up. I've now coded both, and they differ in 4 characters, but I haven't
> the analysis yet (waiting for time to read Julia Clarke's thesis).
Differ in 8 characters in mine.
> > | `--+--Aberratiodontus
> How did you code this vile creature? The photos are horrible. The bones
> to have no surfaces. I tried to code it but gave up.
It certainly limits the amount of codable characters. But you don't need
surfaces for all characters.
> > `--+--+--Parvicursor
> > | `--+--Patagopteryx
> > | `--Songlingornis
Again, the pelvis and hindlimb should remove it from Avialae.
> > `--+--+--Yanornis
> > | `--Ornithurae
> > `--+--Ambiortus
> > `--+--Apsaravis
> > `--Yixianornis
> How did *Yanornis* end up closer to Ornithurae than the other 3?
The fact it lacks a posterodorsal dentary process (unlike Apsaravis). I
expect this area to be better after I split Ornithurae.
Undergraduate, Earth and Space Sciences
University of Washington
The Theropod Database - http://students.washington.edu/eoraptor/Home.html