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Coelurosaur Analysis Update for Dilong

Well, I suppose it's about time for an analysis update, coinciding with the
description of Dilong.  At this point, my analysis is in the middle of a
huge change, which is why I haven't reported much since May.

I systematically examined every published numerical coelurosaur analysis
(and several unpublished ones in theses) and created a list of every
character used (combining where appropriate).  The result is 210 more
cranial, 34 more mandibular, 6 more dental, 65 more axial, 48 more pectoral,
47 more humeral, 31 more radial/ulnar, 14 more carpal, 70 more manual,  28
more ilial, 19 pubic, 23 ischial, 37 femoral, 27 tibial/fibular, 25 tarsal,
65 pedal, and 11 integumentary characters.  Some of these will be rejected
for numerous reasons, but adding them to my old 245 characters means my
analysis will have over 1000 characters once this stage is done.

Right now, I'm only coding the new cranial characters, which means my
analysis has 455 characters.  But I've only coded these additional 210
characters for the carnosaurs, tyrannosauroids and a few basal coelurosaurs,
so far.  There are sporadic codings of other taxa, but not many.  In
addition, I've quantified 127 of these new characters, which means they
can't be coded for any taxa until I can code them for all taxa (see below).
So my analysis effectively has 328 characters.

My plan for quantitative characters is to follow Theile's (1993) method.
First, the minimum and maximum values are found among taxa.  Let's say I'm
coding metacarpal I/II ratios, and (using made up numbers) the lowest is
Ichthyornis, at 20%, while the highest is Ornithomimus at 105%.  Now I
follow this equation-
Xs = 10x (X-20)/(105-20)
Xs is the character state, while X is the ratio of whatever taxon I'm
coding.  Say I'm coding Deinonychus, with a ratio of 40%.  It would be coded
state 2.  Every quantitative character ends up with 10 states, which are
completely objective.  Then to make sure the 10 points of possible variation
aren't weighted more than the 2 points of variation a qualitative character
gets, quantitative characters all get a weight of 1/10.  This also prevents
possible errors in measurement from mattering much.

What else is new since last time
- Dilong, Labocania, "Tanycolagreus" (thanks to Carpenter) and Hwang's new
Ukhaa Tolgod troodontid added.
- Mononykinae broken into Mononykus, Shuvuuia and Parvicursor.
- Oviraptoridae broken into Oviraptor, "Rinchenia", Citipati, IGM 100/2112
(Lu et al.'s 2002 'Ingenia sp.'), Conchoraptor, ZPAL MgD-I/95 (PDW's
'Oviraptor yanshini'), Khaan, "Ingenia" and Heyuannia.
- A lot of new data on ornithomimosaurs (Kobayashi's thesis), Coelurus and
Ornitholestes (Carpenter) and numerous taxa (thanks to Senter).

And besides the huge coding and quantifying job described above, I'm also in
the process of-
- Breaking up Ornithomimidae into Gallimimus, IGM 100/987, Struthiomimus,
Ornithomimus and Dromiceiomimus.
- Breaking up Ornithurae into Hesperornithes and Ichthyornis.
- Adding that new enantiornithine from CJES (they're taking as long to
update their site as JVP).

So, here's the 90% consensus of 201670 most parsimonious trees-

   |  `--+--Allosaurus
   |     `--+--Dryptosaurus
   |        `--+--YPM 1996
   |           `--Acrocanthosaurus
      |  |--Fukuiraptor
      |  `--+--Megaraptor
      |     `--"Tanycolagreus"
      |  `--Therizinosaurus
         |  `--+--Labocania
         |     `--+--Bagaraatan
         |        |--Aviatyrannus
         |        `--+--+--Eotyrannus
         |           |  `--SMNS 58023
         |           `--+--+--Gorgosaurus
         |              |  `--Albertosaurus
         |              `--+--Daspletosaurus
         |                 `--+--Tarbosaurus
         |                    `--Tyrannosaurus
            |  |  `--Nqwebasaurus
            |  `--+--Sinosauropteryx
            |     `--+--NGMC 2124
            |        `--+--Huaxiagnathus
            |           `--'Borsti'

|  |  `--+--Alvarezsaurus
|  |     `--+--Shuvuuia
|  |        `--Mononykus
|  `--+--Pelecanimimus
|     `--+--"Grusimimus"
|        `--+--Harpymimus
|           `--+--Shenzhousaurus
|              `--+--Garudimimus
|                 `--+--+--Anserimimus
|                    |  `--Deinocheirus
|                    `--+--Sinornithomimus
|                       `--+--Archaeornithomimus
|                          `--Ornithomimidae
   |  `--+--Nothronychus
   |     `--+--Alxasaurus
   |        `--+--+--Beipiaosaurus
   |           |  `--Neimongosaurus
   |           `--+--Segnosaurus
   |              `--+--Erlikosaurus
   |                 `--Nanshiungosaurus
   `--+--+--+--Caudipteryx zoui
      |  |  `--Caudipteryx sp. nov.
      |  `--+--Yixianosaurus
      |     `--+--Incisivosaurus
      |        `--+--Protarchaeopteryx
      |           `--+--Caenagnathidae
      |              `--+--Microvenator
      |                 `--+--+--Nomingia
      |                    |  `--+--IGM 100/2112
      |                    |     `--Heyuannia
      |                    `--+--"Rinchenia"
      |                       `--+--"Ingenia"
      |                          `--+--+--Citipati
      |                             |  `--Khaan
      |                             `--+--Conchoraptor
      |                                `--+--ZPAL MgD-I/95
      |                                   `--Oviraptor

|  `--+--Archaeopteryx
|     `--Wellnhoferia
`--+--Ukhaa Tolgod troodontid
      |  `--+--Sinovenator
      |     `--+--Sinusonasus
      |        `--+--IGM 100/44
      |           `--+--Byronosaurus
      |              `--+--Sinornithoides
      |                 `--+--Saurornithoides mongoliensis
      |                    `--+--Saurornithoides junior
      |                       `--Troodon
         |  `--Shenzhouraptor
         `--+--+--Microraptor gui
            |  `--+--Microraptor zhaoianus
            |     `--Cryptovolans
            `--+--NGMC 91
                        `--+--IGM 100/1015
                                    |  `--+--Utahraptor
                                    |     `--Velociraptor
                                       |  `--Unenlagia

|  `--+--Yandangornis
|     `--Avimimus
      |  `--+--Confuciusornis
      |     `--Changchengornis
                        |  |  `--Longirostravis
                        |  `--+--Iberomesornis
                        |     `--+--Eocathayornis
                        |        `--+--Aberratiodontus
                        |           `--+--Liaoningornis
                        |              `--Eoalulavis
                           |  `--+--Neuquenornis
                           |     `--Enantiornis
                                 |  `--+--Patagopteryx
                                 |     `--Songlingornis
                                    |  `--Ornithurae

So everything's looking normal except that mess between carnosaurs and
tyrannosauroids, Dryptosaurus, the deinonychosaurian birds, Avimimus,
Parvicursor and a few minor things.

Additionally, the following taxa were used to make these trees, but deleted
from the consensus tree because they had extremely varying positions.
- Mirischia was a basal tyrannosauroid.
- Variraptor (holotype only) was a basal tyrannosauroid.
- Itemirus was a dromaeosaurid.
- Pyroraptor was a dromaeosaur.
- Richardoestesia was a basal coelurosaur.

Dilong is a basal tyrannosauroid, but this is not supported by many
characters- naris anteriorly positioned; fused nasals; nasals anteriorly
convex in section; pneumatic articular; preacetabular notch in ilium.

Mickey Mortimer
Undergraduate, Earth and Space Sciences
University of Washington
The Theropod Database - http://students.washington.edu/eoraptor/Home.html