[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
RE: What, if anything, is _Apatosaurus_ (Was: Ceratops (was RE: Pterosaur diversity (was: Re: Waimanu)))
Michael Mortimer writes:
>> 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.
One of these days, I am going to write an extended rant on character
weighting. Bottom line: I think the current unweighted-characters
convention amounts to an agreement to bury our heads in the sand.
>>>> 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.
That is very interesting. Re-reading Wilson and Upchurch (2003), I
see that what they actually say is just:
Based on the evidence given above, the genus
_Titanosaurus_ is invalid and co-ordinate suprageneric
Linnean taxa must likewise be abandoned.
There's no appeal to authority -- just an unsupported assertion.
In fact, so far as I can tell, W&U don't quote the ICZN at all in this
paper other than on p. 140 where they mention that names erected in
dissertations are not considered valid.
/o ) \/ Mike Taylor <firstname.lastname@example.org> http://www.miketaylor.org.uk
)_v__/\ "He looks around; he sees angels in the architecture, spinning
in infinity" -- Paul Simon, "Call Me Al"