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RE: What, if anything, is _Apatosaurus_ (Was: Ceratops (was RE: Pterosaur diversity (was: Re: Waimanu)))
Mike Taylor wrote-
The moment you
see one of those honking great cervical ribs, you know what you're
dealing with instantly. So how can it be that in a cladistic
analysis, such an obviously distinctive character counts for no more
than, say, an unobtrustive rugosity on the lateral face of the distal
part of pedal phalange II-2? That's just wrong.
Well, these apomorphies weren't decided by a cladistic analysis, but I agree
weighting is a tricky issue.
> Using Wilson and Upchurch's criteria, very few sauropod genera
> would be valid.
Really? What are the criteria that you allude to exactly? That each
valid genus should be diagnosed by at least one autapomorphy? I would
think that most sauropod genera have that.
Nick Pharris answered this well.
>> 3. If we consider names ending -idae (etc.) to be "family-level"
>> and therefore governed by the ICZN, then Wilson and Upchurch
>> (2003) are right that Titanosauridae must also die;
> Er, why?
Because (early in the argument) I posited that _Titanosaurus_ is
rightly considered a domen dubium. If you contest that assumption,
the rest of the argument doesn't follow.
But I noted that the ICZN says NOTHING about nomina dubia. A taxon should
merely be "well known" if it has a family-level group named after it.
Titanosaurus is well known, wouldn't you say? Which dinosaur worker hasn't
heard of it? I really don't know why Wilson and Upchurch (2003) started the
whole 'family-level taxa can't be based on nomina dubia' myth. Find the
part of the ICZN that says that. I don't think it exists.