Re: New PaleoBios paper - diplodocoid phylogenetic taxonomy

[mike@miketaylor.org.uk (Mike Taylor)]

> Date: Mon, 03 Oct 2005 13:39:00 -0500
> From: "Tim Williams" <twilliams_alpha@hotmail.com>
> 
> [Kind words snipped.]
>
> These kind of housekeeping papers are indispensable.  I'd like to
> see the same thing done for basal sauropodomorphs and
> non-neornithine birds (get out the antacid....).

Well, the latter has largely been done --

        Padian, K., J. R. Hutchinson and T. R. Holtz, Jr.  1999.
        Phylogenetic definitions and nomenclature of the major
        taxonomic categories of the carnivorous Dinosauria
        (Theropoda).  Journal of Vertebrate Paleontology 19:69-80.

Which is available on-line at

        http://www.rvc.ac.uk/Staff/jhutchinson/documents/JRH15.pdf

And also --

        Holtz, Thomas. R., Jr. (1996). Phylogenetic Taxonomy of the
        Coelurosauria (Dinosauria: Theropoda).  J. Paleont. 70(3),
        pp. 536-538.

(Not on-line to the best of my knowledge, though BioOne may have it.)

> The Diplodocoidea/Diplodicimorpha lends itself to this kind of PT
> study, given that (like the Titanosauriformes) the monophyly of this
> group is well-supported.

... except that _Haplocanthosaurus_ (and a few others) could easily be
in either :-)

> Diplodocoidea originally included Nemegtosauridae (now universally
> regarded as titanosaurs); thus Taylor and Naish (2005) neatly
> excised _Nemegtosaurus_ (and its eponymous clade) from the
> definition.

Actually, that's Wilson and Sereno's (1998) definition that we
recommend; not a new one.

> Martin-Rolland, V. (1999).  Les sauropodes chinois, Revue de
> PalÃobiologie.  18: 287-315.

Now that is a paper that _really_ needs to go on the Polyglot
Paleontologist site!

> One way around this is to define Mamenchisauridae to be
> (_Mamenchisaurus_ + _Omeisaurus_, but not _Diplodocus_ or
> _Saltasaurus_), such that the definition includes an internal
> caveat.  This way, if _Mamenchisaurus_ and _Omeisaurus_ are found to
> be paraphyletic relative to 'higher' sauropods, the clade
> self-nullifies.

Ye-es.  I think it's a matter of philosophy whether you like such
magic disappearing clades or not.  I am not personally wild about them.

 _/|_    ___________________________________________________________________
/o ) \/  Mike Taylor  <mike@miketaylor.org.uk>  http://www.miketaylor.org.uk
)_v__/\  "If you are a fascinating writer, then you follow a deeper set
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         you need to follow the normal rules until you get fascinating"
         -- Greg Gunther.