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Re: JON & ORNITHOLESTES



Darren Naish wrote (in a somewhat aggressive tone):
>Jon Wagner has written us a long load of text on big 
>non-coelurosaurian theropods. And he says...
        Hello?

>> I don't think anyone who talks about a monophlyetic 
>> Carnosauria thinks it includes tyrannosaurs, except maybe Norell and 
>> Novacek.
>
>What's your basis for this statement Jon? 
        Which statement Darren? "except maybe Norell and Novacek." Ok,
Novacek is not an author on the reference, my error. However:
        REFERENCE: Clark, Altangerel and Norell, 1994.
        P.30: "For these reasons [enumerated in the preceeding paragraph] we
are skeptical of the main conclusion of Holtz's analysis - that
Tyrannosauridae are members of Maniraptor[formes]..."
        Also it should be noted that Carnosauria including tyrannosaurs was
a part of the big cladogram around which the new AMNH halls were designed. I
believe Dr. Novacek had something to do with this, didn't he?

        "I don't think anyone who talks about a monophlyetic Carnosauria
thinks it includes tyrannosaurs"?
        WORKER:         REFERENCE (full citations at the end of this post):
        Holtz:          Holtz 1994, and pers. com.
        Sereno:         Sereno et al. 1994, 1996
        Sues:           Sereno et al. 1994, Sues 1997 
        Currie:         Mackovicky and Currie 1998 (tacit acceptance?)
        Sanz:           Perez-Moreno et al. 1994
        Russell:        Russell and Dong 1993
        Dong:           Russell and Dong 1993
        Buffetaut:      Buffetaut et al. 1996
        There are probably more, but I think that's enough...

        Granted, of these people, Holtz is the ONLY "official dinosaur
worker" I have heard(/read about) recently discussing the taxon Carnosauria
(except on the dino list). I assume his partners in taxonomy, Hutchinson and
Padian, do talk about a taxon Carnosauria, although I can't speak for what
they think it contains. The workers above are folks who exclude tyrannosaurs
from Carnosauria (as defined phylogenetically), given their views on
theropod phylogeny as expressed in their publications. They are not,
however, workers who necessarily explicitly invoke the taxon Carnosauria.
Carnosauria exists whether they refer to it or not, it being all taxa more
closely related to _Allosaurus_ than to modern birds. I am NOT trying to
deliberately twist the issue around here, the phylogeny is inextricably
bound within the taxonomy (at least for me and practitioners of phylogenetic
taxonomy). 

        BTW: In the list above, it is quite possible that I have
over-interpreted tacit acceptance as belief. However, I was merely
discussing individuals who had *talked* about the subject. Anyone with a
different take on this, please feel free to speak up.

>You shouldn't have said this Jon - Sereno et al. (1996 - the paper 
>that describes the new _Carcharodontosaurus_ material 
>and _Deltadromeus_) does include a diagnosis of 
>Allosauroidea (in the notes and references section).
        I am very well aware of this, Darren. And it is just that, a
DIAGNOSIS. Sitting here with the paper in front of me I still do not see a
DEFINITION. As you well know, definition and diagnosis are seperate
characteristics of a taxon. I cannot discern the membership of Allosauroidea
from the diagnosis (although I guess I could try). Therefore, as the segment
you quoted from my post goes, "no priority". Because he does not provide a
definition, Sereno's usage of the taxon should not be considered to have
priority, IMHO (and in other's oppinions, apparently, Hutchinson pers.
com.). Labelling nodes without providing a definition ("blind") is difficult
to deal with, since others may (indeed they appear to, see Benton 1997)
simply copy your labels without necessarily understanding your usage, or
worse, they may have to try and interpret your definitions. How many times
have you seen a stem-based taxon labelled at a node?. This is all quite
"annoying", but not insurmountable. - Should I not have said this, Darren?

>And Jon - if you are interested in the systematics and morphology of 
>carnosaurs, you MUST get hold of Harris (1998). 
        Thanks Darren. I do have interest in these subjects, and I have
indeed aquired the volume in question. Unforunately, I must take more of an
interest in my thesis right now, so I am content to marvel at the
illustrations and read small excerpts.

>Something Jon does not note 
        Probably because Jon didn't KNOW...
        Well, I suppose a "little bird" told me once, but I hardly think I
should be held accountable for every whispered secret on a private e-mail
sent on the 12th of July 1996. In fact, I remembered most of phylogeny, just
not the use of Carnosauria...

>is Phil Currie's endorsement of a monophyletic Carnosauria. 
        And, I should point out, from the last "secret communication" I
recieved concerning Currie's phylogeny he DIDN'T believe that this group
included tyrannosaurs (see above). Granted, that was from 1996, and it's
heresay...

>Though (to my knowledge), Currie has not 
>published an in-depth analysis of the relationships of these 
>theropods (yet), he has said that _Ceratosaurus_, sinraptorids and 
>allosaurids do belong together 
        Actually, by phylogenetic taxonomy, this group would be the
Ceratosauria. Thanks to Dr. Holtz for pointing this out.

        Wagner

        REFERENCES:
Buffetaut, E., V. Suteethorn, and H. Tong 1996. The earliest known
tyrannosaur from the Lower Cretaceous of Thailand. Nature 381: 689-691

Clark, J. M., P. Altangerel and M. A. Norell 1994. The Skull of
_Erlicosaurus andrewsi_, a Late Cretaceus [sic] "Segnosaur" (Theropoda:
Therizinosauridae) from Mongolia. American Museum Novitates 3115: 39 pp., 13
figures

Holtz 1994      -       I hope everyone has this reference. I can get it for
you if you don't, but you might not want to advertise your failing on the
list. ;)

Mackovicky , P. J., and P. J. Currie 1998. The presence of a furcula in
tyrannosaurid theropods, and its phylogenetic and functional implications.
Journal of Vertebrate Paleontology 18(1): 143-149

Perez-Moreno, B. P., J. L. Sanz, A. D. Buscalioni, J. J. Moratalla, F.
Ortega, and D. Rasskin-Gutman 1994. A unique multitoothed ornithomimisaur
dinosaur from the Lower Cretaceous of Spain. Nature 370: 363-367

Russell, D. A. and Dong Z.-M. 1993. The affinities of a new theropod from
the Alxa Desert, Inner Mongolia, People's Republic of China. Canadian
Journal of Earth Sciences 30: 2107-2127

Sereno, P. C., J. A. Wilson, H. C. E. Larsson, D. B. Dutheil, H.-D. Sues
1994. Early Cretaceous dinosaurs from the Sahara. Science 266: 267-271

Sereno, P. C., D. B. Dutheil, M. Iarochene, H. C. E. Larsson, G. H. Lyon, P.
M. Magwene, C. A. Sidor, D. J. Varricchio, J. A. Wilson 1996. Predatroy
dinosaurs from the Sahara and Late Cretaceous faunal differentiation.
Science 272: 986-991

Sues, H.-D. 1997. On _Chirostenotes_, a Late Cretaceous oviraptorsaur
(Dinosauria: Theropoda) from western North America. Journal of Vertebrate
Paleontology 17(4): 698-716
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    Jonathan R. Wagner, Dept. of Geosciences, TTU, Lubbock, TX 79409-1053
    "See that lump on his jaw? ...it's called 'lumpy jaw'!" - Steve Irwin