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The plausibility of alternative placements for theropod taxa
David Marjanovic wrote-
>> I should try adding the holotype to a non-maniraptoriform supermatrix I've
>> been working on (including all codings from Smith et al., 2007; Tykoski,
>> 2005; Carrano and Sampson, 2007; Rauhut, 2003; Azuma and Currie, 2000;
>> Allain, 2002; Ezcurra and Novas, 2006; etc.).
> Wow. Is that supermatrix your thesis?
Nah. As you know, ensuring a preexisting matrix is coded correctly and has
objective character states takes as much time as creating your own matrix. So
I would never use such a supermatrix for more than just seeing where the
currently published matrices suggest taxa belong. I made it because I was
curious about ceratosaur and coelophysoid monophyly. So far it contains all
the characters, taxa and codings from-
Smith et al.'s (2007) large theropod matrix in the Cryolophosaurus paper. (347
Tykoski's (2005) matrix focusing on coelophysoids and ceratosaurs from his
thesis. (95 additional characters)
Carrano and Sampson's (2007) ceratosaur matrix. (39 additional characters)
Excurra and Novas' (2006) matrix focusing on coelophysoids from their
Zupaysaurus paper. (61 additional characters)
Rauhut's (2003) theropod matrix, including Xu et al.'s (2006) codings for
Guanlong and Dilong, Lamanna's (2004) codings for Megaraptor, and Yates' (2005)
codings for Dracovenator and several other taxa. (20 additional characters)
Allain's (2002) matrix focusing on spinosauroids and carnosaurs from his
Dubreuillosaurus paper (7 additional characters)
Azuma and Currie's (2000) matrix from their Fukuiraptor paper (31 additional
characters), which is basically the same as Currie and Carpenter's (2000)
Langer and Benton's (2006) matrix of basal dinosaur relationships (25
Yates' (2006) sauropodomorph matrix (134 additional characters so far), in
order to get good representation of the theropod sister group.
I only checked character accuracy when two matrices disagreed, and generally
didn't code taxa for characters nobody else had. Thus while superior to the
studies listed above, it's by no means a finished product and represents more
of a compilation of prior work than my own work. Coding 131 taxa for 763
characters the proper way is too large a project for me at the moment- that's
what my coelurosaur analysis is and it's taking years. :) Obvious future steps
include adding Holtz et al.'s (2004), Carrano et al.'s (2005), Sereno et al.'s
new carcharodontosaurid stuff, and the info from the Lophostropheus,
Tyrannotitan and Mapusaurus papers. Important taxa to add would be
Scleromochlus, Lewisuchus, Sacisaurus, Eucoelophysis, Agnostiphys,
Chindesaurus, Sarcosaurus, Chuandongocoelurus, Berberosaurus, Brontoraptor,
Spinosaurus, Marshosaurus, Erectopus, Gasosaurus, Lourinhanosaurus,
Yangchuanosaurus, Mapusaurus, Saurophaganax, Huaxiagnathus, Sinocalliopteryx,
Aniksosaurus, Juravenator, Nedcolbertia, Nqwebasaurus, Santanaraptor and
Scipionyx. Also, coding Falcarius, Protarchaeopteryx, Incisivosaurus,
Sinovenator, Mei, Buitreraptor and/or Rahonavis in addition to the two birds
and two derived dromaeosaurids would quite probably affect the placement of
Ornitholestes and Bagaraatan.
Current results are-
`--+--Ornithischia (5 taxa)
|--Sauropodomorpha (4 taxa)
| | |--Dilophosaurus wetherilli
| | |--"Dilophosaurus" sinensis
| | `--Cryolophosaurus
| `--+*-Shake'n'Bake taxon
| | `--"Syntarsus" kayentakatae
| | `--Spinostropheus
| | |--Genusaurus
| | |--Masiakasaurus
| | `--Laevisuchus
| | |--Majungasaurus
| | `--Indosuchus
| | `--+--Piveteausaurus
| | |--Dubreuillosaurus
| | `--Afrovenator
`--Paraves (4 taxa)
I forced various constraint trees to estimate the rough liklihood that
alternative hypotheses are correct. I tried to test as many possibilities as I
could recall were ever suggested in the last thirty years, with some older ones
in there for good measure. Of course, with near certain coding errors, not
every taxon coded for every character possible, and missing characters and
taxa, these numbers shouldn't be taken as the final word. But a topology that
needs 5 more steps is far more likely to be true than one that needs 20 more
steps. So, starting with the most likely alternatives and working to the the
least likely ones, with my subjective divisions of how liklihood correlates to
extra steps in the trees...
The current tree, with the following non-consensus aspects-
Silesaurus as a basal saurischian. Never suggested before, but all the data
from Langer and Benton (2006) which kept it out of Dinosauria was included.
Eoraptor and herrerasaurids as successively closer outgroups to Avepoda, as
suggested by Sereno et al. (1993). This despite the fact Langer and Benton's
data were included.
Dilophosaurids as coelophysoids, as in Paul (1988) and most cladistic analyses.
With Rauhut (2003), Yates (2005) and Smith et al. (2007) all contributing to
the data, it certainly seems to support coelophysoid dilophosaurids.
"Syntarsus" kayentakatae being closer to Segisaurus than to Megapnosaurus, as
suggested by Tykoski (2005).
Spinostropheus clading with Elaphrosaurus to the exclusion of other
ceratosaurs, as in Lapparent (1960) and Carrano and Sampson (2007).
Ceratosaurus closer to abelisauroids than Elaphrosaurus is, as in Holtz (2000).
Ilokelesia being a carnotaurine, as in Carrano and Sampson (2007).
Streptospondylus being a basal tetanurine outside the
Spinosauroidea+Avetheropoda clade, which hasn't been suggested before.
Poekilopleuron being a basal spinosauroid, which has not been suggested before.
Torvosaurus being closer to spinosaurids than to eustreptospondylids, as in
The generally basalmost tetaurines Piatnitzkysaurus, Condorraptor,
Xuanhanosaurus and "Szechuanoraptor" being closer to avetheropods than
spinosauroids are. This has been suggested previously for Piatnitzkysaurus
(Novas, 1992) and "Szechuanraptor" (Chure, 2000).
Monolophosaurus being outside Avetheropoda, as in Smith et al. (2007).
Carcharodontosaurids being outside Avetheropoda, as in Coria and Salgado (1995).
Sinraptor being closer to Allosaurus than to Neovenator or Acrocanthosaurus,
which I don't think has been suggested before.
Neovenator being closer to allosaurids than carcharodontosaurids, as in Hutt et
Acrocanthosaurus being closer to allosaurids than carcharodontosaurids, as in
Stovall and Langston (1950).
Fukuiraptor being a coelurosaur, as in Longrich (2001).
Deltadromeus being a tyrannosauroid, which hasn't been suggested yet. Though
the possibly synonymous Bahariasaurus has (Paul, 1988; Chure, 2000).
Dilong being closer to birds than tyrannosaurids, as in Turner et al. (2007).
This leaves no reason to postulate secondarily featherless tyrannosaurids.
Mirischia and Aristosuchus being closer to Dilong than Compsognathus (as in
Niaish, online 2006; though he had Dilong as a tyrannosauroid).
Guanlong being closer to birds than tyrannosaurids (and Dilong!), which hasn't
been suggested before and is frankly the opposite of what I expected.
Siamotyrannus being a compsognathid, which hasn't been suggested before.
Bagaraatan being a maniraptoran, as in Rauhut (2003).
Forcing Elaphrosaurus to be closer to abelisaurids than Ceratosaurus is (as in
Holtz, 1994) adds only one step.
Forcing Streptospondylus to be sister to Eustreptospondylus (as in Allain,
2001) adds only one step. Streptospondylus moves into Spinosauroidea, whose
topology remains the same.
Forcing Piatnitzkysaurus to be outside the spinosauroid-avetheropod clade (as
in Rauhut, 2003 and Smith et al., 2007) adds only one step. Condorraptor is
its sister taxon in this case, as in Smith et al. (2007), and Xuanhanosaurus
and "Szechuanoraptor" move along with it (as in Rauhut, 2003).
Forcing Neovenator to be a carcharodontosaurid (as in Rauhut, 2003 and others)
adds one step. The (Acrocanthosaurus(Sinraptor+Allosaurus)) clade remains,
while Neovenator is the sister to Megaraptor in basal Carcharodontosauridae
Forcing Siamotyrannus to be a carnosaur (Pharris, 1997) adds one step. The
topology among paraphyletic carnosaurs is unchanged and it is a sinraptorid
(which is where Pharris predicted it would be).
Forcing Mirischia to be a compsognathid (as in Martill et al., 2000) adds one
Forcing Coelophysis and Megapnosaurus rhodesiensis to be sister taxa (as in
Tykoski, 2005 and others) adds 2 steps.
Forcing Eustreptospondylus to be closer to spinosaurids than Torvosaurus (as in
Smith et al., 2007) adds 2 steps. The other eustreptospondylids move with
Forcing Poekilopleuron to be a torvosaurid (as in Galton and Jensen, 1979) adds
2 steps. The newly formed Torvosauridae are still sister to Spinosauridae.
Forcing Chilantaisaurus to be a tyrannosauroid (as in Paul, 1988) adds 2 steps.
Interestingly, this is rather close to where "Chilantaisaurus" maortuensis
Forcing Allosauroidea (allosaurids, carcharodontosaurids and sinraptorids) (as
in Sereno et al., 1996) to be monophyletic adds 2 steps. The topology within
it stays the same, so that carcharodontosaurids are most basal and Sinraptor is
nested within allosaurids. Monolophosaurus is still basal to Avetheropoda,
while Fukuiraptor and Siamotyrannus are coelurosaurs.
Forcing Monolophosaurus to be a spinosauroid (as suggested by Headden on the
DML, 2002) adds 2 steps. It is the most basal spinosauroid in these trees.
Forcing Fukuiraptor to be sister to Siamotyrannus (as in Holtz et al., 2004)
adds 2 steps. The two are basal coelurosaurs outside Tyrannoraptora.
Forcing Procompsognathinae sensu Sereno (Procompsognathus + Segisaurus) (as in
Sereno and Wild, 1992) adds 3 steps.
Forcing Dracovenator to be closer to Ceratosauria + Tetanurae than to
Coelophysoidea (as in Yates, 2005) adds 3 more steps. Oddly, it ends up as a
spinosaurid, while Cryolophosaurus is sister to Ceratosauria+Tetanurae and
"Dilophosaurus" sinensis is a basal tetanurine. Dilophosaurus wetherilli stays
Forcing Deltadromeus to be a ceratosaur (as suggested by Sereno et al., 2002)
adds 3 more steps. It falls in the Elaphrosaurus + Spinostropheus clade.
Forcing Carnotaurus and Majungasaurus to clade to the exclusion of Rajasaurus
(as in Wilson et al., 2003) adds 3 steps.
Forcing Sinraptoridae to be basal to Avetheropoda (as in Paul, 1988) adds 3
steps. In this tree, carcharodontosaurids are coelurosaurs.
Forcing Fukuiraptor to be a carnosaur (as in Azuma and Currie, 2000 and Holtz
et al., 2004) adds 3 more steps. It is placed sister to Allosaurus, while
carcharodontosaurids and Monolophosaurus are still outside Avetheropoda.
Forcing Aristosuchus to be a coelurid (as in Lydekker, 1889) adds 3 steps. In
this tree, Guanlong is also a coelurid.
Forcing Coelurus to be a compsognathid (as in Lull, 1911; technically,
Compsognathus would be a coelurid...) adds 3 steps.
Forcing Eusaurischia to exclude herrerasaurids and Eoraptor (as in Langer and
Benton, 2006) adds only 4 more steps. These trees have the same topology as
Langer and Benton's paper, with Silesaurus outside Dinosauria, Eoraptor closer
to eusaurischians than herrerasaurids are, and Guaibasaurus as a basal theropod.
Forcing Procompsognathus to be the most basal avepod (as in Paul, 1988) adds 4
Forcing Cryolophosaurus to be a basal tetanurine (as in Smith et al., 2005)
adds 4 more steps. In these trees, "Dilophosaurus" sinensis is its sister
Forcing Piatnitzkysaurus to be a spinosauroid (as in Holtz et al., 2004) adds 4
steps. It falls out (often with Condorraptor) as the basalmost spinosauroid,
even more basal than Poekilopleuron.
Forcing Neovenator to be the sister taxon to Allosaurus (as in Hutt et al.,
1996) adds 4 steps. Acrocanthosaurus, Sinraptor and Megaraptor form successive
outgroups, while carcharodontosaurids are coelurosaurs.
Forcing Coelurus to be a maniraptoran (as in Gauthier, 1986) adds 4 steps. It
is directly basal to Ornitholestes in this tree.
Forcing Proceratosaurus to be sister to Ornitholestes (as in Paul, 1988) adds 4
steps. This pairing ends up in basal Maniraptora.
Forcing Megapnosaurus rhodesiensis and "Syntarsus" kayentakatae to be sister
taxa (as in Rowe, 1989) adds 5 more steps. In these trees, Procompsognathus is
closest to Megapnosaurus sensu lato, with Coelophysis one step further out.
Segisaurus is now in the Zupaysaurus-Liliensternus mess.
Forcing Deltadromeus to be sister to ornithomimosaurs (as in Rauhut, 2003) adds
5 more steps.
Forcing Spinostropheus to be sister to abelisaurs (but keeping Elaphrosaurus as
the basalmost ceratosaur; as in Sereno et al., 2004) adds 5 more steps.
Forcing Megaraptor to be a spinosauroid (as suggested by Calvo et al., 2004)
adds 5 steps. It ends up sister to Torvosaurus+Spinosauridae.
Forcing Siamotyrannus to be a tyrannosauroid (as in Buffetaut et al., 1996)
adds 5 steps. Guanlong and Dilong are still closer to birds than to
Forcing Bagaraatan to be a tyrannosauroid (as in my analyses from 2003 onward)
adds 5 steps.
Forcing Torvosaurus to be closer to eustreptospondylids than to spinosaurids
(as in Sereno et al., 1994) adds 6 steps. In these trees, the four 'basalmost
tetanurines' (Piatnitzkysaurus, Xuanhanosaurus, Condorraptor and
"Szechuanoraptor") all move outside the spinosauroid-avetheropod clade.
Forcing Afrovenator to be outside the Eustreptospondylus + Torvosaurus +
Spinosauridae clade (as in Sereno et al., 1994) adds 6 steps. Dubreuillosaurus
and Piveteausaurus stay with Afrovenator, and Torvosaurus is still closer to
spinosaurids than Eustreptospondylus.
Forcing Monolophosaurus to be a carnosaur (as suggested by Zhao and Currie,
1993) adds 6 steps. It is the basalmost carnosaur, and the topology of
Allosauroidea is the same as when its monophyly is forced, with Fukuiraptor and
Siamotyrannus still coelurosaurs.
Forcing Ornitholestes to be a coelurid (as in Matthew and Brown, 1922) adds 6
Forcing Ornitholestes to be outside Maniraptoriformes (as in Paul, 1988) adds 6
Forcing Proceratosaurus to be a tyrannosauroid (as suggested by me on the DML)
adds 6 steps.
Forcing Dilophosaurus to be sister to Ceratosauria + Tetanurae (as in Rauhut,
2003) adds 7 more steps. In these trees, Dracovenator is sister to
Dilophosaurus, while "Dilophosaurus" sinensis and Cryolophosaurus form a clade
one node closer to ceratosaurs+tetanurines.
Forcing Deltadromeus to be a noasaurid (as in Wilson et al., 2003) adds 7 more
Forcing Xuanhanosaurus to be a torvosaurid adds 7 steps.
Forcing Acrocanthosaurus to be a carcharodontosaurid (as in Sereno et al.,
1996) adds 7 steps. In these trees, Neovenator is a more basal
carcharodontosaurid, while Sinraptor and Allosaurus form a clade sister to
Carcharodontosauridae. Monolophosaurus and Megaraptor are outside
Avetheropoda, Fukuiraptor and Siamotyrannus are coelurosaurs, and Tyrannotitan
is basal to Carcharodontosaurus+Giganotosaurus.
Forcing Guanlong (as in Xu et al., 2006), Dilong (as in Xu et al., 2004) and/or
Mirischia (as in Naish, online 2006) to be tyrannosauroids adds 7 steps. They
form a clade with Aristosuchus to the exclusion of Tyrannosauridae, with
"Alashansaurus" as the basalmost tyrannosauroid.
Forcing Compsognathus to be outside Tyrannoraptora (as in Holtz, 1994) adds 7
Forcing Proceratosaurus to be basal to Coelurus and tyrannosauroids (as in
Holtz, 2000) adds 7 steps.
Possible but not well supported-
Forcing Liliensternus to be more closely related to Dilophosaurus than to
Coelophysis (as in Paul, 1988) adds 8 steps. Dracovenator (and sometimes
Lophostropheus) joins this 'halticosaur' clade, while Zupaysaurus and
Gojirasaurus stay closer top Coelophysis. Cryolophosaurus and "Dilophosaurus"
sinensis are then closer to Ceratosauria+Tetanurae.
Forcing "Szechuanoraptor" to be an allosaurid (as in Molnar et al., 1990) adds
Forcing Afrovenator to be closer to Avetheropoda than Piatnitzkysaurus,
Torvosaurus, Eustreptospondylus and Spinosauridae (as in Holtz, 2000) adds 8
steps. Dubreuillosaurus and Piveteausaurus stay in Spinosauroidea.
Forcing spinosauroids to be carnosaurs (as in Rauhut, 2003 and older sources
with more extensive Carnosauria's) adds 8 steps. Fukuiraptor also falls out in
this clade, though Siamotyrannus remains a coelurosaur.
Forcing Zupaysaurus to be closer to ceratosaurs+tetanurines than to
coelophysoids (as in Arcucci and Coria, 1997) adds 9 steps. As in that study,
dilophosaurids end up even closer to birds.
Forcing Piatnitzkysaurus to be a basal carnosaur (as in Harris, 1998) adds 9
Forcing Coelurus to be a tyrannosauroid (as in Senter, 2007) adds 9 steps. The
topology is similar to when Guanlong is forced to be a tyrannosauroid, with
Coelurus outside the Dilong+Guanlong+Aristosuchus+Mirischia clade.
Forcing Coelurus to be basal to tyrannoraptorans (as in Makovicky, 1995) adds 9
Forcing Bagaraatan to be outside Tyrannoraptora (as in Holtz, 2000) adds 9
Forcing Proceratosaurus to be a ceratosaurid (as in Huene, 1926) adds 9 steps.
Forcing "Szechuanoraptor" to be a sinraptorid (as in Paul, 1988) adds 10 steps.
Forcing Piatnitzkysaurus to be a eustreptospondylid (as in Paul, 1988) adds 10
steps. It ends up sister to other eustreptospondylids.
Forcing Sinraptor to be basal to allosaurids and carcharodontosaurids within
Allosauroidea (as in Harris, 1998) adds 10 steps. Oddly, this forces
spinosauroids to be carnosaurs, in addition to Monolophosaurus. While
Neovenator and Acrocanthosaurus are carcharodontosaurids, Fukuiraptor is an
Forcing Dilong to be a compsognathid (as suggested by Olshevsky I believe,
online) adds 10 steps.
Forcing Eoraptor to be a basal theropod, but herrerasaurids to be outside
Eusaurischia (as in Ezcurra, 2006) adds 11 steps.
Forcing Indosaurus to be a tyrannosaurid (as in Chatterjee, 1978) adds 11 steps.
Forcing Coelurus to be basal to avetheropods (as in Paul, 1988) adds 11 steps.
Oddly, instead of being just outside Avetheropoda, it moves to the base of the
Tetanurae with Tugulusaurus.
Forcing Aristosuchus to be a compsognathid (as in Naish, 2002) adds 12 steps.
Forcing Tyrannosaurus to be a maniraptoran (as in Sereno, 1997) adds 12 steps.
Forcing coelophysoids to be ceratosaurs (as in Gauthier, 1986) adds 13 more
steps. In these trees, Cryolophosaurus and "Dilophosaurus" sinensis are basal
Forcing Elaphrosaurus to be a coelophysoid (as in Paul, 1988) adds 13 more
steps. It falls out with Spinostropheus between Liliensternus+Lophostropheus
and Zupaysaurus+derived coelophysids. Amusingly right where Paul put it.
Forcing spinosaurids to be more basal than Piatnitzkysaurus,
Eustreptospondylus, Afrovenator and Torvosaurus (as in Holtz, 2000) adds 13
steps. Spinosauroidea becomes paraphyletic to Avetheropoda, with Torvosaurus,
Eustreptospondylidae, Poekilopleuron and Piatnitzkysaurus successively closer
Forcing Sinraptor to be closer to carcharodontosaurids than to Allosaurus (as
in Coria and Currie, 2002) adds 13 steps. I these trees, Neovenator and
Acrocanthosaurus are carcharodontosaurids, while Allosaurus is the basal
Forcing Compsognathus to be a tyrannosauroid (as in Olshevsky, 1991) adds 13
steps. This also makes Sinosauropteryx, Guanlong, Coelurus, Dilong, Mirischia
and Aristosuchus tyrannosauroids.
Forcing Ilokelesia to be outside Noasauridae+Abelisauridae (as in Coria and
Salgado, 2000) adds 14 steps.
Forcing Afrovenator to be sister to Allosauroidea (as in Rauhut, 2003) adds 14
steps. Dubreuillosaurus and Piveteausaurus stay in Spinosauroidea.
Forcing Ornitholestes outside Tyrannoraptora (as in Holtz, 1994 and others)
adds 14 steps.
Forcing Procompsognathus to be outside Dinosauria (as in Allen, 2004) adds 15
Forcing Deltadromeus to be closer to birds than Ornitholestes (as in Sereno et
al., 1996) adds 15 more steps, mainly from moving Ornitholestes down the tree.
Forcing Piatnitzkysaurus to be an allosaurid (as in Molnar et al., 1981) adds
Near certainly untrue-
Forcing Ceratosaurus to be closer to tetanurines than abelisaurids are (as in
Carrano and Sampson, 1999) adds 18 steps. Elaphrosaurs and noasaurids stay
Forcing Compsognathus outside Avetheropoda (as in Paul, 1988) adds 18 steps.
Forcing Piatnitzkysaurus to be an abelisaur (as in Currie and Zhao, 1993) adds
Forcing Monolophosaurus to be sister to Guanlong (as suggested by Carr, 2006)
adds 22 steps. The pair are placed as coelurosaurs just outside Tyrannoraptora.
Forcing Cryolophosaurus to be a carnosaur (as in Sereno et al., 1996) adds 23
more steps. It changes the tree a lot, with most basal tetanurines moved into
Forcing Monolophosaurus to be a tyrannosauroid (as suggested by me on the DML)
adds 24 steps. In these trees, Guanlong and Dilong are still closer to birds
than to tyrannosaurids, though Siamotyrannus is a tyrannosauroid.
Forcing Guanlong to be a carnosaur (as in Carr, 2006) adds 24 steps.
Siamotyrannus, Fukuiraptor, Dilong and Aristosuchus are also carnosaurs in
Forcing Tyrannosaurus to clade with ornithomimosaurs (as in Huene, 1923) adds
Forcing Torvosaurus to be a ceratosaur (as in Britt, 1991) adds 26 steps. It
emerges outside the elaphrosaur-ceratosaurid-abelisauroid clade, but other
spinosauroids stay in Tetanurae.
Forcing Guanlong to be a carnosaur sister taxon to Monolophosaurus (as in Carr,
2006) adds 27 steps.
Forcing Acrocanthosaurus to be a spinosaurid (as in Walker, 1964)adds 30 steps.
Spinosaurids are moved into Carnosauria.
Forcing Elaphrosaurus to be an ornithomimosaur (as in Galton, 1982) adds 33
Forcing abelisaurids to be sister to carcharodontosaurids (as in Novas, 1997)
adds 35 steps. The clade ends up in Ceratosauria, and Acrocanthosaurus and
Neovenator remain in Carnosauria.
Forcing Zupaysaurus to be a tetanurine (as in Arcucci and Coria, 2003) adds 37
Forcing Megaraptor to be a dromaeosaurid (as suggested in Rauhut, 2003) adds 38
Forcing Abelisaurus to be a carcharodontosaurid (as suggested by Lamanna et
al., 2002) adds 39 steps.
Forcing Monolophosaurus to be an ornitholestiid (as in Paul, 2002) adds 40
steps. Ornitholestes and Proceratosaurus are moved outside Avetheropoda with
Forcing Ornitholestes to be an allosaurid (as in Paul, 1988) adds 41 steps.
Forcing Sinosauropteryx outside Coelurosauria (as in Longrich, DML 2000) adds
Forcing the less extensive Carnosauria of Molnar et al., 1990
(Piatnitzkysaurus, Allosaurus, carcharodontosaurids and tyrannosaurids) adds 44
steps. Spinosauroids, Monolophosaurus and Sinraptor form successively closer
outgroups to Carnosauria. The Allosauridae of Molnar is paraphyletic to
tyrannosaurids, with Piatnitzkysaurus most basal and carcharodontosaurids most
Russell and Dong's (1993) crazy topology of
adds 45 steps, mainly from moving ornithomimosaurs so basally.
Bakker et al.'s (1988) topology of
(Cerato(Allo(Dromaeo(Acrocantho(Ornithimimidae,Tyrannosauridae))))) adds 53
Forcing abelisaurids to be tetanurines closer to birds than Torvosaurus (as in
Forster, 1999) adds 55 steps. Noasaurids and Deltadreomeus clade with
Forcing the Allosauria of Paul (Ornitholestes, Proceratosaurus, Allosaurus,
carcharodontosaurids and tyrannosaurids) adds 56 more steps. Though
constrained to be outside Paul's Allosauria, Piatnitzkysaurus, spinosauroids,
Monolophosaurus and sinraptorids end up forming successively closer outgroups
to it. Paul's ornitholestiines end up closer to tyrannosaurids than to
allosaurids, and include Dilong and Guanlong as well.
Forcing abelisauroids to be torvosaurids within Tetanurae (as in Paul, 1988)
adds 57 steps. Spinosaurids and Monolophosaurus join the torvosaur part of
this clade, while elaphrosaurs hang back with Ceratosaurus.
Forcing spinosaurids to be coelophysoids closest to dilophosaurs (as in Paul,
1988) adds 60 steps.
Forcing a traditional Carnosauria of sinraptorids, Torvosaurus, spinosaurids,
abelisaurids, eustreptospondylids, carcharodontosaurids, allosaurids and
tyrannosaurids (as in Kurzanov, 1989) adds 82 steps. Unlike Kurzanov's
topology, abelisaurids emerge as most basal, Spinosauroidea is intact, and
sinraptorids are sister to allosaurids.
Forcing paravians outside of Dinosauria (as Feduccia, Martin, etc. suggest)
adds 87 steps. Even though I specified Allosaurus as a dinosaur, all
coelurosaurs are more parsimoniously "birds" when this happens.
Forcing spinosaurids and birds to be sister taxa (as in Elzanowski and
Wellnhofer, 1992) adds 93 steps. The clade ends up in a very basal coelurosaur
position (ignoring for the moment that birds aren't with the rest of what's
Forcing Huene's original Carnosauria-Coelurosauria phylogeny of 1923, where
coelophysids, ornithomimids, tyrannosaurids and Ceratosaurus are coelurosaurs,
while Allosaurus and spinosauroids are carnosaurs adds 97 steps.
Forcing Torvosaurus and Poekilopleuron to be more closely related to
Plateosaurus than to coelophysoids and coelurosaurs (as in Galton and Jensen,
1979) adds 101 steps. The rest of Spinosauroidea, as well as Ceratosauria and
Carnosauria end up joining the two 'megalosaurs' to form a large-bodied
theropod clade sister to Sauropodomorpha. Within Saurischia, coelophysoids are
more closely related to this clade than coelurosaurs.