Tuesday, June 7, 2011

Theropod Working Group matrix recoded

As part of my large in progress paper, and the description of a new paravian I'm coauthoring, I've been going through the TWG matrces.  The first was by Norell et al. in 2001, and included many less taxa and characters than the current ones do.  Their original topology (based on running the matrix through PAUP, it is a bit different than the one they published) using their higher taxonomy was-

|--Sinraptor 
|--Allosaurus 
`--+--Tyrannosauridae
   |  |--Albertosaurus 
   |  `--Tyrannosaurus 
   `--Coelurosauria
      |--Ornithomimosauria
      |  |--Pelecanimimus 
      |  |--Harpymimus 
      |  |--Garudimimus 
      |  `--+--Gallimimus 
      |     `--Struthiomimus 
      `--Maniraptora
         |--Ornitholestes 
         `--+--Alvarezsauridae
            |  |--Alvarezsaurus 
            |  `--+--Patagonykus 
            |     `--Mononykinae
            |        |--Shuvuuia 
            |        `--Mononykus 
            `--+--+--Dromaeosauridae
               |  |  |--Sinornithosaurus 
               |  |  |--Unenlagia 
               |  |  `--+--Achillobator 
               |  |     |--Utahraptor 
               |  |     |--Dromaeosaurus 
               |  |     |--Deinonychus 
               |  |     |--Velociraptor 
               |  |     |--Tsaagan
               |  |     |--Adasaurus 
               |  |     `--Saurornitholestes 
               |  `--Avialae
               |     |--Rahonavis ostromi
               |     `--+--Archaeopteryx 
               |        `--Confuciusornis 
               `--+--Troodontidae
                  |  |--Sinornithoides 
                  |  `--+--Byronosaurus 
                  |     `--+--Troodon  

                  |        `--+--Saurornithoides 
                  |           `--Zanabazar
                  `--+--Therizinosauroidea
                     |  |--Alxasaurus
                     |  |--Erlikosaurus 

                     |  `--Segnosaurus
                     `--Oviraptorosauria
                        |--+--Chirostenotes 

                        |  `--Avimimus 
                        `--+--Microvenator 
                           `--+--Caudipteryx 
                              `--Oviraptoridae
                                 |--Oviraptor 

                                 |--Rinchenia
                                 |--IGM 100/42
                                 |--Conchoraptor 

                                 `--"Ingenia" 


The result of recoding all the taxa is-

|--Sinraptor
|--Allosaurus
`--Coelurosauria
   |--Tyrannosauridae
   |  |--Gorgosaurus
   |  `--Tyrannosaurus
   `--+--Ornitholestes
      `--Maniraptoriformes
         |--Ornithomimosauria
         |  |--Garudimimus
         |  `--+--Harpymimus
         |     `--Ornithomimidae
         |        |--Gallimimus
         |        `--Struthiomimus
         `--Maniraptora
            |--+--Alvarezsauridae
            |  |  |--Pelecanimimus
            |  |  |--Alvarezsaurus
            |  |  `--+--Patagonykus
            |  |     `--Parvicursorinae
            |  |        |--Shuvuuia
            |  |        `--Mononykus
            |  `--Therizinosauroidea
            |     |--Segnosaurus
            |     `--+--Alxasaurus
            |        `--Erlikosaurus
            `--+--Caudipteryx
               `--+--Oviraptorosauria
                  |  |--Avimimus
                  |  |--Chirostenotes
                  |  |--Microvenator
                  |  `--Oviraptoridae
                  |     |--Oviraptor
                  |     `--+--IGM 100/42
                  |        `--"Ingeniinae"
                  |           |--Conchoraptor
                  |           `--+--Rinchenia
                  |              `--"Ingenia"
                  `--Paraves/Eumaniraptora
                     |--Dromaeosauridae
                     |  |--Sinornithosaurus
                     |  |--Utahraptor
                     |  |--Dromaeosaurus
                     |  |--Tsaagan
                     |  |--Deinonychus
                     |  |--Achillobator
                     |  |--Adasaurus
                     |  |--Velociraptor
                     |  `--Saurornitholestes
                     `--Avialae
                        |--Sinornithoides
                        |--Troodontidae
                        |  |--Byronosaurus
                        |  `--+--Saurornithoides
                        |     `--+--Zanabazar
                        |        `--Troodon
                        `--+--Archaeopteryx
                           `--Ornithurae
                              |--Confuciusornis
                              `--Unenlagiinae
                                 |--Rahonavis
                                 `--Unenlagia


Notice there are a couple odd things probably caused by a lack of characters- Alxasaurus sister to Erlikosaurus (one more step needed to change), Caudipteryx outside Oviraptorosauria (also one more step). Yet there are also some interesting plausible groupings such as the derived Harpymimus, alvarezsauroid Pelecanimimus, alvarezsaur-therizinosaur clade, basal Oviraptor, Zanabazar+Troodon and  ornithurine Unenlagiinae.  Note also that it resembles the standard topology more than TWG's original in a non-maniraptoriform Ornitholestes, paravian Troodontidae and more basal Caudipteryx.

For those interested, the following number of additional steps are needed for-
Carnosaurian tyrannosaurids as in Molnar et al. (1990)- 4. 
Maniraptoran tyrannosaurids as in Sereno (1999)- 8.
Ornitholestes as an allosaurid (Paul, 1988)- 11. 
Ornitholestes less derived than tyrannosaurids- 3.
Ornitholestes as a maniraptoran- 2.
Ornitholestes as a dromaeosaurid as in Makovicky (1995)- 11.
An ornithomimosaur-alvarezsaurid clade- 2.
Alvarezsaurids as basal maniraptorans outside therizinosaurs+oviraptorosaurs+paravians- 3. 
Alvarezsaurids as basal paravians- 2.
Alvarezsaurids as avialans- 11.
Alvarezsaurids as ornithurines- 10 (13 with Alvarezsaurus too, which otherwise goes to Oviraptorosauria).
Alvarezsaurids and therizinosaurs joining with ornithomimosaurs as in Sereno (1999)- 5.
Enigmosauria- 2.
Oviraptorosauria being closer to birds than dromaeosaurids or troodontids- 10.
Arctometatarsalia as in Holtz (1994)- 45.
"Pneumatocrania" as in Holtz (1992/1994)- 28.
Bullatosauria- 22.
Deinonychosauria- 15(!).
Archaeopteryx being a troodontid - 4.
Dromaeosaurids being ornithurines (closer to birds than Archaeopteryx as in Paul)- 3 (troodontids also join them)
Unenlagiines being dromaeosaurids- 1.
Senter's (2007) eudromaeosaur topology- 8.
Longrich and Currie's (2009) eudromaeosaur topology- 9.Russell and Dong's (1994) crazy topology- 23.

Of course, without important taxa like basal tyrannosauroids, the mess of basal coelurosaurs, Deinocheirus, Shenzhousaurus, Haplocheirus, Falcarius, Beipiaosaurus, Protarchaeopteryx, Incisivosaurus, Pedopenna, Buitreraptor, Mahakala, Shanag, Microraptor, Austroraptor, Mei, Sinovenator, Jinfengopteryx, scansoriopterygids, Anchiornis, Shenzhouraptor, Dalianraptor, Jixiangornis and omnivoropterygids, those numbers aren't too important.  But adding these taxa and the new characters of more recent TWG analyses is the next step...

1 comment:

  1. Indeed the Groupings of Pelecanimimus and the Unenlagines is very interesting.
    I hope those relationships can be further cleared up if more data is added...

    ReplyDelete