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RE: Ceratops analyzed in the Sampson et al. (2010) matrix



Jaime Headden wrote-

>   Not to place any sort of sense of non-achievement on Mickey's doings, but I 
> do not agree that he should publish even close to this. First of all, it 
> would certainly help that he examines the material first hand; the dearth of 
> actual description the holotype of *Ceratops montanus* has received to date 
> almost certainly deserves this. A close second is to actually consider the 
> effects of ontogeny on a ceratopsian cladogram: While the effects are known 
> in theropod cladograms, although not extensively studied throughout 
> theropods, it would be extremely important to note that what may be 
> diagnostic may also be juvenile and non-diagnostic as an adult (one could 
> diagnose juveniles of *Triceratops prorsus* as diagnostic taxa because of 
> their unique morphological features in the frill, horns, etc.). This 
> rushing-to-publication would almost certainly be jumping the gun, when there 
> is much, much to be handled before anything of this sort should be done, and 
> we're not even talking about verifying the codings of the other taxa, yet!

I have to agree with Jaime here (gasps are no doubt heard in the audience ;) 
).  I don't think firsthand examination is necessary to code in this case, due 
to the nature of the characters.  Nor do I think ontogeny is particularly 
important for Ceratops, at least no more so than for the average ceratopsid.  
Sure the Triceratops-Torosaurus synonymy throws a wrench into things, but you 
don't see people rushing out to question all the other ceratopsids' validity, 
so it would be unfair to give Ceratops that extra hurdle.  Ceratops was an 
adult individual based on the completely fused exoccipital and basioccipital 
and had an estimated frill width of 880 mm (based on occipital condyle 
diameter), which isn't much smaller than the adult holotype of Chasmosaurus 
irvinensis (1050 mm).  Incidentally, this also dismisses Tim's concern about 
ontogeny and request to code Eoceratops' holotype (though it would still be 
interesting).  I also disagree that all the codings need to be checked for the 
other taxa, at least ideally.  Sure, miscodings in theropod analyses (at least) 
are often abundant, but having to recheck authors' codings everytime you run 
their analysis is akin to reinventing the wheel.  Think of how many times the 
Theropod Working Group matrix has been modified for instance, yet no one 
expects it to be rechecked every time a new Yixian coelurosaur is plugged into 
it.  However, I will note that my perusal of Sampson et al.'s characters 
suggested that several should have their states reordered and ran as ordered 
characters (such as curvature characters, since straight is by definition 
intermediate between procurved and recurved).

Instead, the reason I wouldn't publish this is first, I'm not a ceratopsian 
researcher.  I don't follow the literature closely, as is shown by me only 
noticing yesterday that Mojoceratops shouldn't have been named.  If there are 
subtleties to the characters or Ceratops' morphology (and there usually are), 
they'd go right past me.  Just as important, there was basically no work 
involved.  Anyone could look at Hatcher's monograph and plug in a few codings.  
It was more a demonstration that analyzing Ceratops could be done, that 
Ceratops does indeed fall out most parsimoniously as a ceratopsine ceratopsid 
and that it's not obviously undiagnostic.  As such it was a counter to the 
assertion Ceratops can't be placed phylogenetically within Ceratopsidae and 
Ceratopsinae and would create a polytomy, so shouldn't be used as an internal 
specifier.  While I think I accomplished that goal satisfactorily, just 
plugging a taxon into a pre-existing matrix isn't really publication-worthy, 
even if it is an important genus.  Ceratops deserves to be scrutinized and 
redescribed by somebody who specializes in ceratopsids.

Mickey Mortimer