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Coelurosaur Analysis Update featuring Buitreraptor



Since the last update http://dml.cmnh.org/2005May/msg00137.html , a lot has been accomplished.

- Appalachiosaurus, Buitreraptor, Hesperornithes, Ichthyornis and Iaceornis added.
- New data added for Nothronychus, Nemegtia and Eoenantiornis.
- All qualitative cranial characters coded for pygostylian birds, and many coded for other maniraptoriformes.
- Character weights equalized.


This last point is important. Many people don't realize that making an ordered character multistate serves to give it greater weight. Say you have "pubic angle - <90 degrees posterior (0); >90 degrees posterior (1)". A basic propubic vs. opisthopubic character. It takes one step to get from one extreme to the other. Now add in mesopuby as state 1, and make opisthopuby state 2. Because it's ordered, it takes 2 steps to get from propubic to opisthopubic now (you have to go through mesopuby). You've just weighted pubic angle compared to a bistate character. What's the solution? Corrective weighting. You need to give pubic angle half the weight your bistate character has. Then it takes the same amount of steps to get from one extreme to the other in both cases. So I did this to all my characters.

The 90% majority rule consensus of the first 50118 mpt's-

|--Monolophosaurus
`--+--+--Acrocanthosaurus
  |  `--+--Sinraptor
  |     `--+--Allosaurus
  |        `--Fukuiraptor
  `--+--+--Dryptosaurus
     |  `--+--Megaraptor
     |     `--+--+--Coelurus
     |        |  `--Calamosaurus
     |        `--+--Tanycolagreus
     |           `--+--"Alashansaurus"
     |              `--Labocania
     `--+--+--Dilong
        |  |--Eotyrannus
        |  |--Itemirus
        |  |--Iliosuchus
        |  |--Stokesosaurus
        |  `--+--+--Gorgosaurus
        |     |  `--+--Albertosaurus
        |     |     `--Appalachiosaurus
        |     `--+--Daspletosaurus
        |        `--+--Tarbosaurus
        |           `--+--Bagaraatan
        |              `--+--Aviatyrannis
        |                 `--Tyrannosaurus
        `--+--NGMC 2124
           `--+--Ornitholestes
              `--+--Proceratosaurus
                 `--+--+--Nqwebasaurus
                    |  `--+--Huaxiagnathus
                    |     `--Sinosauropteryx
                    `--+--Scipionyx
                       `--+--Compsognathus
                          `--+--+--Borsti
                             |  `--+--+--Archaeornithoides
                             |     |  `--+--Pelecanimimus
                             |     |     `--"Grusimimus"
                             |     `--+--+--Anserimimus
                             |        |  `--+--Harpymimus
                             |        |     `--Shenzhousaurus
                             |        `--+--Garudimimus
                             |           `--+--Sinornithomimus
                             |              `--+--Archaeornithomimus
                             |                 `--Ornithomimidae
                             `--Maniraptora

|--+--+--+--Falcarius
|  |  |  `--Neimongosaurus
|  |  `--+--Beipiaosaurus
|  |     `--+--Alxasaurus
|  |        `--+--Nanshiungosaurus
|  |           `--+--Segnosaurus
|  |              `--Erlikosaurus
|  `--+--IVPP V11309
|     |--Nothronychus
|     |--Sapeornis
|     `--+--Omnivoropteryx
|        `--+--Caudipteryx
|           `--+--Avimimus
|              `--+--+--Shixinggia
|                 |  `--Nomingia
|                 `--+--+--Incisivosaurus
|                    |  `--Protarchaeopteryx
|                    `--+--+--Therizinosaurus
|                       |  `--+--Nemegtia
|                       |     `--Heyuannia
|                       `--+--+--Caenagnathidae
|                          |  `--+--Citipati
|                          |     `--Deinocheirus
|                          `--+--Ingenia
|                             `--+--+--Microvenator
|                                |  `--Oviraptor
|                                `--+--+--NXMV
|                                   |  `--Rinchenia
|                                   `--+--Khaan
|                                      `--+--Conchoraptor
|                                         `--ZPAL MgD-I/95
`--+--+--Erlianosaurus
  |  `--+--Patagonykus
  |     `--+--Alvarezsaurus
  |        `--+--Parvicursor
  |           `--+--Shuvuuia
  |              `--Mononykus
  `--+--+--+--+--Archaeopteryx
     |  |  |  `--Wellnhoferia
     |  |  `--+--Rahonavis
     |  |     `--+--Buitreraptor
     |  |        `--Scansoriopteryx
     |  `--+--Ukhaa Tolgod troodontid
     |     `--+--Sinovenator
     |        `--+--Byronosaurus
     |           `--+--Sinusonasus
     |              `--+--IGM 100/44
     |                 `--+--Yixianosaurus
     |                    `--+--Sinornithoides
     |                       `--+--Troodon
     |                          `--+--Saurornithoides junior
     |                             `--Saurornithoides mongoliensis
     `--+--Jinfengopteryx
        `--+--+--+--Shenzhouraptor
           |  |  `--+--Jixiangornis
           |  |     `--Yandangornis
           |  `--+--Mei
           |     `--+--Graciliraptor
           |        `--+--NGMC 91
           |           `--+--+--Microraptor gui
           |              |  `--+--Microraptor zhaoianus
           |              |     `--Cryptovolans
           |              `--+--Richardoestesia
           |                 `--+--Sinornithosaurus
           |                    `--+--Bambiraptor
           |                       `--+--Adasaurus
           |                          |--Utahraptor
           |                          |--Atrociraptor
           |                          |--IGM 100/1015
           |                          |--Velociraptor
           |                          |--Pyroraptor
           |                          |--Deinonychus
           |                          |--+--Achillobator
           |                          |  `--Dromaeosaurus
           |                          `--+--Unenlagia
           |                             `--+--Variraptor
           |                                `--Saurornitholestes
           `--+--+--Confuciusornis
              |  `--Changchengornis
              `--+--Jibeinia
                 `--+--Longipteryx
                    `--+--Protopteryx
                       `--+--+--Eoenantiornis
                          |  `--LP-4450-IEI
                          `--+--Vescornis
                             `--+--Concornis
                                |--Enantiornis
                                |--Noguerornis
                                |--Neuquenornis
                                |--+--Boluochia
                                |  `--Gobipteryx
                                |--+--+--Longirostravis
                                |  |  `--Sinornis
                                |  `--+--Iberomesornis
                                |     `--+--Eocathayornis
                                |        `--+--Aberratiodontus
                                |           `--+--Liaoningornis
                                |              `--Eoalulavis
                                `--+--+--Patagopteryx
                                   |  `--+--Ambiortus
                                   |     `--+--Apsaravis
                                   |        `--Iaceornis
                                   `--+--Songlingornis
                                      `--+--Yanornis
                                         `--+--Yixianornis
                                            `--+--Hesperornithes
                                               `--+--Ichthyornis
                                                  `--YPM 1996

There seem to be some "improvements"
- "Alashansaurus" and Labocania are sister taxa.
- 'Iliosuchids' are tyrannosauroids.
- Pelecanimimus and "Grusimimus" are ornithomimosaurs.
- Protarchaeopteryx sister to Incisivosaurus.
- Parvicursor is an alvarezsaurid.
- Saurornithoides is monophyletic (finally!).
- Jibeinia basal to birds with 2-3-1 manual phalangeal formula.
- Enantiornithies closer to being monophyletic.
- Yanornithids close together.

Some changes which may have support-
- Deinocheirus no longer an ornithomimosaur (Makovicky et al., 2004).
- Sapeornis and Omnivoropteryx as oviraptorosaurs.
- Alvarezsaurids are paravians (the first time it's ever happened in my matrix!)
- Jinfengopteryx sister to Eumaniraptora (and incidentally close to both troodontids and archaeopterygids)
- Mei and Asian long-tailed birds as basal deinonychosaurs.


And some things which would generally be considered wrong.
- Labocania no longer a tyrannosauroid.
- Aviatyrannis and Bagaraatan as tyrannosaurines.
- Borsti as a basal arctometatarsalian.
- Nothronychus and Erlianosaurus not therizinosaurs.
- Neimongosaurus sister to Falcarius.
- Caenagnathidae, Microvenator and Oviraptor nested deeply within Oviraptoridae.
- Byronosaurus very basal within Troodontidae.


But it's interesting to note the situation around Buitreraptor. It comes out close to Rahonavis (as in Makovicky et al.) and scansoriopterygids (and no, I didn't code any manual characters for it, as the ironically scansoriopterygid-like hands on the mount are fake). Then this clade is sister to archaeopterygids (which I previously noted had Makovicky et al.'s unenlagiine synapomorphies), then to troodontids. Intriguingly, Shenzhouraptor and its relatives are where unenlagiines are located in Makovicky et al.'s tree. So I just switched flying raptors. ;) In fact, the bases of the troodont, dromaeosaur and bird lines are all volant. I suppose you have volant omnivoropterygids over in Oviraptorosauria too. Unenlagia though, is still a dromaeosaur.

Note I didn't really test Unenlagiinae though, as only one of the three synapomorphies is in my matrix at the moment. Of the two that aren't though-
1. The dorsally concave postacetabular process is present in Archaeopteryx and Scansoriopteryx too, so that would actually be a synapomorphy of that odd clade. Unenlagia and Achillobator would then be dromaeosaurs that developed it convergently.
2. Mesopuby is seen in Archaeopteryx and Scansoriopteryx too, as well as other taxa near the maniraptoran stem (Jinfengopteryx, Patagonykus, Falcarius, etc.). Again, Unenlagia and Achillobator would parallel it within Dromaeosauridae.
So I think my tree explains these at least equally well, despite not incorporating them.


As for placing Buitreraptor closer to dromaeosaurs than troodontids, my analysis includes 5 of 7 dromaeosaur characters listed by Makovicky et al. I don't know the detailed distribution of stalked dorsal parapophyses or a ginglymoid metatarsal III yet, so can't say how they'd optimize in my tree. Still, I don't think a dromaeosaur Buitreraptor is very strongly supported, nor a dromaeosaur Rahonavis. But who knows. Btw, it takes 7 more steps to make a Rahonavis + Archaeopteryx + Buitreraptor clade (excluding Unenlagia) in Makovicky et al.'s matrix. Confuciusornis becomes a member, and the whole thing becomes sister to troodontids.

Mickey Mortimer