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Re: my phylogeny, as of SVP'96 (long)



At 12:54 PM 3/18/97 -0600, Jonathan R. Wagner wrote:
>
>        Note that, with the following tree topology:
>        (Acrocanthosaurus, (Sinraptoridae, Allosaurus))
>        
>        And the following taxon definitions:
>        Allosauridae = {+ _Allosaurus_, + _Acrocanthosaurus_}
>        Allosauroidea = {+ _Allosaurus_, + _Sinraptor_}
>        
>        Allosauridae is a more inclusive taxon than Allosauroidea!
>(Translation for layfolk: the "superfamily" Allosauroidea is included within
>the "family" Allosauridae.)

Indeed.  Which is why some are arguing the definitions for the "families"
involved (which have NOT been formally defined phylogenetically) should be:

Allosauridae = {+ _Allosaurus_, - _Sinraptor_}
Sinraptoridae = {+ _Sinraptor_, - _Allosaurus_}
so that Allosauroidea is necessarily more inclusive than Allosauridae (i.e.,
it minimally includes the non-allosaurid _Sinraptor_).

However, this has the 'drawback' of making "Carcaharodontosauridae" a
subdivision of Allosauridae.

>[       As I understand, the actual definition is:
>        Allosauroidea = {+ Allosauridae, + Sinraptoridae}

Allosauroidea has only been phylogenetically defined within the Holtz and
Padian 1995 abstract.  Those authors (in the paper on which the abstract is
based) use the first of the definitions who offer (i.e., {+ _Allosaurus_, +
_Sinraptor_}).

>        A) Does any one have any references on the "tradition" of attempting
>to maintain some semblance of Linnean structure (eg. trying to keep
>"families" less inclusive than "superfamilies") in Phylogenetic Taxonomy.
>Not keeping ranks, keeping the naming tradition.

No literature on that I've seen.  Some (such as the founders of the system
itself, de Queiroz and Gauthier, specifically use as the prime example the
inclusion of a traditional lizard family within another traditional lizard
family).

Thomas R. Holtz, Jr.
Vertebrate Paleontologist     Webpage: http://www.geol.umd.edu
Dept. of Geology              Email:th81@umail.umd.edu
University of Maryland        Phone:301-405-4084
College Park, MD  20742       Fax:  301-314-9661