Re: [dinosaur] Diplodocus status

[Tim Williams <tijawi@gmail.com>]

John D'Angelo <dangelojohne@gmail.com> wrote:

> Since you brought up the distinction between nomenclature and taxonomy, bear 
> in mind that the concept of a type species is a nomenclatural concept, not a 
> taxonomic one.

Yes, but it is still a *species*.  A type species is a type AND a
species.  Which brings me to...

Mickey Mortimer <mickey_mortimer111@msn.com> wrote:

> Since when are undiagnostic species not species?  Are you saying the 
> Diplodocus longus type individual wasn't part of an interbreeding population 
> of organisms, or
> whatever species concept you follow?

No, I'm not saying that - that would be silly.  The type of _D.
longus_ certainly came from a once-living species.  (Actually, the
same is true of any fossil that came from a living organism - even
_Aachenosaurus_, a 'dinosaur' based on petrified wood).  But I don't
see how your question is relevant.  I'd say that for any genus that
contains multiple species, each individual species should be
diagnostic at the species level - including the type species.  This
should be true irrespective of whichever species concept you prefer.
When we say _D. longus_ is a separate species to _D. carnegii_, it
should be because we have anatomical evidence that they represented
distinct species in the Late Jurassic.