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RE: Titanoceratops, giant ceratopsian from New Mexico

1. Presentations at SVP should not be cited, and I'm sure the views espoused by 
Scanella and Horner in conference and print will be fully expanded upon in the 

2. It is problematic to argue that you see intermediates "everywhere" when the 
paper used to support the conversion of *Torosaurus* to *Triceratops* fails to 
do so in an explicit, provable manner:

a. Scannella and Horner do not differentiate specific variation, but rather use 
generic lumping, and extend this to species without explanation or data.

b. Tabulated variation and text in Scannella and Horner show a marked 
distinction between "Torosaurus" and "Triceratops" morphologies, with LITTLE 
overlapping specimens. When present, said overlapping specimens are considered 
"unusual" or "aberrant" but rather than demonstrative of the argument against 
which Scannella and Horner appear to be arguing.

c. Variation on a specific level is never quantified, permitting the reviewer 
the ability to follow a logical progression. Instead, the authors promote the 
view of generic condensation, and apply the specimens to this without providing 
a means of testing it.

TL;DR: Two people arguing that "my taxon is unique, yours isn't" doesn't 
promote science.


Jaime A. Headden
The Bite Stuff (site v2)

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)

"Ever since man first left his cave and met a stranger with a
different language and a new way of looking at things, the human race
has had a dream: to kill him, so we don't have to learn his language or
his new way of looking at things." --- Zapp Brannigan (Beast With a Billion 

> Date: Thu, 30 Dec 2010 12:19:02 +0000
> From: df9465@yahoo.co.uk
> To: dinosaur@usc.edu
> Subject: Re: Titanoceratops, giant ceratopsian from New Mexico
> It's astonishing how many of "Titanoceratops"'s characters are known to vary
> (strongly) ontogenetically; I see no reason to split off the OMNH 
> Pentaceratops
> into a new genus and species: it is entirely consistent with being a mature
> Pentaceratops. Should we be splitting up all the ceratopsid growth series into
> different taxa? They certainly have different morphologies, but then that's
> because animals change as they grow.
> I am coming ever closer to the view that we're going to see a schism in 
> dinosaur
> science; at least in ceratopsid workers, with one side splitting all 
> ontogenetic
> and stratigraphic morphs into different taxa, and the other studying 
> ontogenetic
> shifts through time. Taxa are testable hypotheses using ontogenetic and
> stratigraphic data. if you are just using morphology, then it's a judgement
> call, and not much different from the way taxonomy was conducted 100 years 
> ago.
> I can't see it is possible to continue with one side trying to convince the
> other: look at Longrich's discussion of Triceratops-Torosaurus. I hesitate to
> call Triceratops-Torosaurus a complex problem (I think it actually simplifies
> things), but Longrich goes into such little detail it feels very dismissive.
> Saying that there are no intermediates is absurd: we see nothing but
> intermediates with the squamosals and other parts of the skull. Why don't we
> find some parietals with tiny fenestrae (ie. intermediates)? because that's 
> not
> how the fenestrae form, and if you read the papers and look at specimens, 
> you'll
> see it. New specimens are revealing more data on this; but be patient, we
> collected so many new Triceratops (with the essential strat data) it takes 
> time
> to prep them all. It is much more parsimonious if Torosaurus is Triceratops: 
> so
> many of the weird biogeographic and stratigraphic trends that we see fall into
> place.
> To be fair this paper was submitted before Scannella presented at SVP, and 
> other
> talks at SVP (including mine) show some of the conclusions here to be invalid.
> Triceratopsins in the Campani
> e my full critique of this paper for elsewhere.
> D.
> ----------------------------------
> Denver Fowler
> df9465@yahoo.co.uk
> http://www.denverfowler.com
> -----------------------------------
> ----- Original Message ----
> From: Tim Williams 
> To: dinosaur@usc.edu
> Sent: Thu, 30 December, 2010 4:09:52
> Subject: Re: Titanoceratops, giant ceratopsian from New Mexico
> > In case this new advance publication paper has not been mentioned yet:
> >
> > Nicholas R. Longrich (2010) Titanoceratops ouranous, a giant horned dinosaur
> >from the
> > Late Campanian of New Mexico. Cretaceous Research (advance online 
> > publication)
> > doi:10.1016/j.cretres.2010.12.007
> There seems to be a discrepancy in the spelling of the species name
> between the title of the paper (ouranous) and the body of the paper
> (ouranos), with the former having an extra (and unnecessary) 'u'.
> Something to correct before final publication. BTW, the inspiration
> for the species name is Ouranos, the father of the Titans in Greek
> mythology. This is the same dude that gives his name to the planet
> Uranus. Apparently, the etymology is not the same as that of
> _Ouranosaurus_, which comes from the Tuareg name for monitor lizard
> ('ourane'), and is cognate with 'varanus'.
> Anyway, back to _Titanoceratops_ (cool name, IMHO). Aside from
> erecting a new genus for an erstwhile _Pentaceratops_ specimen, the
> paper puts forward a few more taxonomic changes vis-a-vis
> _Triceratops_. The referral of _Torosaurus_ to _Triceratops_ is
> explicitly rejected; a separate diagnosis is provided for each, and
> the "absence of intermediate forms argues that the two are not part of
> an ontogenetic series." On the other hand, _Nedoceratops_
> (=_Diceratops_) and _Ojoceratops_ are referred to _Triceratops_ as
> junior synonyms. For the latter: "the broad, squared-off end of the
> squamosal, putatively a diagnostic feature of “_Ojoceratops_” is
> approached by at least one specimen of _Triceratops_ (_Triceratops
> “serratus”_, AMNH 970)." So I guess _Ojoceratops_ is the problem.
> more so t
> an _T. serratus_, which I assume is safe inside
> _Triceratops_. The status of another new genus, _Tatankaceratops_, is
> given as "problematic". It "preserves a bizarre mixture of characters
> seen in juvenile and adult _Triceratops_", so the specimen is either
> an aberrant _Triceratops_ that stopped growing before reaching full
> size, or a dwarf triceratopsin species. I wouldn't be surprised if
> more taxonomic convulsions are in stall for the Triceratopsini.
> Cheers
> Tim