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Re: SVP Preview



George Olshevsky (Dinogeorge@aol.com) wrote:

<Afaik, ICZN does not recognize phylogenetic definitions, but it does
govern family level taxa. The ending -oidea is standard for superfamilies,
making Megalosauroidea and Spinosauroidea both family level taxa subject
to ICZN rules of synonymy. Even if the clades are rankless, the name
Megalosauroidea has priority over Spinosauroidea, so that when
Spinosauroidea was phylogenetically defined, it was really Megalosauroidea
that was being given the definition.>

  What the ICZN does not govern is the endings of nomina, such as -oidea;
just ending a taxon name thusly does not make it a superfamily, and if I
could remember the name, I could tell you of one small fossil reptile or
mammal "genus" name that ends in -oidea, but I see no one turning it into
a superfamily as a consequence. This suggests that endings have no ranking
significance, and the fact that some taxa have ranks is because they are
explicitly provided. Sereno did not rank Torvosauroidea, nor does he and
his colleagues any other name they have proposed, and nor have Holtz, etc.
Conventionally, Deinonychosauria would be such a name as it includes two
"family"-ranked taxa, Troodontidae and Dromaeosauridae, but this, too, was
not done. And for the better. Once you divorce "rank" from "taxon," it
becomes a whole lot easier to assemble taxa, though relation of names must
be provided in definitions. Linnaean taxonomy only provides a sort of
pseudodefinition in that clades can be "ranked" and thus their relations
are implied by assembly.

  No one has yet answered, probably because it cannot be answered, what
the difference between an order and a class is. If you can, you deserve
the Nobel Prize.

  Cheers,

=====
Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

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