RE: Titanoceratops, giant ceratopsian from New Mexico

[Jaime Headden <qi_leong@hotmail.com>]

  My statements are consistent with a generalistic response to yours, including 
the theroies on the taxonomy of the "*Triceratops* complex" os "species" and 
the genus usage being employed by various authors. You are entirely incorrect 
when you assume that I "don't like the Tor=Trike hypothesis," as I've never 
said anything of the sort. What I've argued, here and elsewhere, has dealt with 
the particulars of the argument, not the end result -- reiterating this gets 
tiresome. It is not that difficult to "get" that an hypothesis can be wrong 
even if its result can be rightly conceived, as long as it is poorly arrived at 
in the present. Similarly, the use of said hypothesis to judge the utility of 
splitting or lumping taxonomy (one of the cruxes of a complex matter here) is 
illogical, as one literally has nothing to do with the other.

  My reply regarded specifically the issue of Scannella and Horner (and your 
support in their work, and your involvement in as-yet unpublished work) follows 
previous condemnation of preconcieved lumping advocated by the authors 
including the [hypothetical] *Pachycephalosaurus* implosion. That it is 
possible -- nay, likely -- for convergence to occur in close lineages is an 
issue for reconstruction of phylogeny, rather than presumptions of phylogeny 
before the fact. Making statements about how some features (such as the 
criticism leveled at the *Torosaurus*/*Triceratops* issue -- ignoring the 
*latus*/*prorsus*/*horridus* problem horrifically ignored by various authors) 
are less meaningful (again, on both sides) shows that the debate is based on a 
pre-concieved, _a priori_ assumption of the end result, a lumping versus 
splitting mentality.

  This has NOTHING to do with my personal thoughts on the existence of a 
separate "generic" entity called *Torosaurus* (which I've never stated in any 
forum, nor spoken to anyone on a personal level). This has to do with 
lumping/splitting -- and the presumption that stratigraphy has a splitter 
effect on species.

Cheers,

Jaime A. Headden
The Bite Stuff (site v2)
http://qilong.wordpress.com/

"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 
Backs)





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> Date: Thu, 30 Dec 2010 14:48:25 +0000
> From: df9465@yahoo.co.uk
> To: dinosaur@usc.edu
> Subject: Re: Titanoceratops, giant ceratopsian from New Mexico
>
> what's the point of your post? You don't answer anything that I posted. I know
> you don;t seem to like the Toro=Trike hypothesis, but like many other people,
> you seem to think that diversity should be the default view. Why? You think
> parietal fenestrae are such a big deal? They are well demonstrated to open up 
> in
> centrosaurines through ontogeny. Squamosal elongation is seen in all
> chasmosaurines through ontogeny, and has been in print for over 20 years. 
> These
> are just the most obvious easy-answer ontogenetic changes: there are many 
> more.
>
> ----- Original Message ----
>
> From: Jaime Headden 
>
> >TL;DR: Two people arguing that "my taxon is unique, yours isn't" doesn't 
> >promote
> >science.
>
> Rubbish. A robust taxonomy is the fundamental underpinning to paleobiological
> interpretation: I don't agree that there are 3 ghost lineages of 
> chasmosaurines
> present during Kirtland time: there is probably only one. this obviously has
> great importance in our interpretation of biodiversity and evolution. I don't
> care whether you have everything as a separate genus or not, it is the number 
> of
> contemporaneous lineages that matters.
>
> D
>
>
>
>
>
> ----------------------------------------
> > 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
> >onto
> 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/
> 7
> >
> >
> > 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
> >
> >
> >
> >
>
>
>