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RE: Editedaceratops, giant ceratopsian from New Mexico

I do not wish to beat a dead horse here, but I realized I missed this message, 
so I am taking some time to reply to it. It involved things I've said, things 
I've said before and had been glossed over, and things that should be said. 
All, of course, with the caveat that this is my (humble? no) opinion. I also 
changed the subject line, largely to avoid a problem: using unpublished 

Denver Fowler wrote:

<Well there you go. So are we destined to see an endless repeat of your 
misreading of the Triceratops work then? I guess so.


No. my comments were to point out that in the paper you haven't read, the 
subject is not discussed adequately, and that understanding ontogeny can 
actually inform on why we see some of the character states exhibited by 
[Editedaceratops - JAH].>

  This stems from a comment I made about the application of the ontogenetic 
work suddenly being applicable to *Pentaceratops* with Longrich's new taxon 
fulfilling a larger, older individual, and how I had not read Longrich's 
reasons for doing so. I will not be reading Longrich's paper (as it is an 
unproofed, unfinalized -- and UNPUBLISHED -- version of the article) until it 
is published, and would comment and invite others to do as well then. Until 
then, as I had made an injunction on this thread before, I suggest not 
discussing papers (especially of a taxonomic nature) before they are published; 
ceasing discussion of unpublished work as valuable to refute said unpublished 
papers, or to reinforce other published papers, is similarly problematic as it 
permits no one to check the data.

  Similarly, I did not misread the *Triceratops* work. I was (thinking, fairly) 
arguing that due to the implied ontogeny in ceratopsians of one stripe that 
there was some nomenclatural (taxonomic) fudging. It does not follow, as 
Denver's reply to Longrich appears to suggest it does, that an ontogeny 
observed among taxa should indicate taxa are synonymous. This is especially 
true if the ontogeny of *Pentaceratops* (unknown so far, nor any published 
histological data of the kind doen for *Triceratops*) differs in the slightest; 
but even if it were identical, and *Pentaceratops* is different from 
*Triceratops*, then it stands to reason that this lineage of chasmosaurines 
should be expected to have identical ontogenies. If so, segregating taxa due to 
ontogeny (or lumping them) becomes further problematic. BUT ... none of this 
has been published. W4TP.

<Garbage. There are less lineages present in the Hell Creek than in Campanian 
units. That's a fact. Whether or not this is indication of slow deterioration 
of dinosauria towards the KT is up for debate, but you'd be hard-pressed to 
find anyone who can demonstrate that immediately prior to the KT there are as 
many hadrosaurs (multiple clades), nodosaurs, centrosaurines, etc than there 
were in the Campanian. Again, my strat work is trying to have some bearing on 
this in the Hell Creek, but you know, it takes longer to write a paper than it 
does to write a critical email.>

  I can argue that, because some authors are summarily reducing taxa in the 
Maastrichtian but are not reducing taxa in the Campanian, that they condense 
one arbitrary set of fossils while unrestricting another. I would argue, and it 
has been in print, that biostratigraphy puts the cart before the horse, 
attempting to impose a diversity model by taxonomic sampling of artificial 
values, without any sense that the levels of taxa being sampled can be both 
over and underinflated due to varying concepts of the use _genera_ and 
_species_. Under this, we can easily impose an anagenetic lineage to all (or 
most of it, and indeed, this too has been proposed) of *Chasmosaurus*, 
transfering various taxa back into *Chasmosaurus belli* and chalk up any 
differences to time and region. Campanian nodosaurs versus Maastrichtian 
ankylosaurs are virtually incomparable: there are more ankylosaurs in the 
Maastrichtian of North America than there are in the Campanian ... what value 
does this have in segregating these groups but to inflate the "lower diversity" 
of the one in time? We should rather simply remark that "There are more 
*Centrosaurinae* in the Campanian than in the Maastrichtian; thus, 
*Ceratopsidae* is _declining_ over time;" unless *Ceratopsidae* and 
*Centrosaurinae* are synonymous, the statement is illogical.

  The deck is stacked simply by altering the labels used.

<What is a "taste" issue? The strat work doesn't necessarily support taxic 
reductionism (another made up term, which I presume means reduction in the 
number of taxa).>

  I clarifed by reasons for using this in my response to David Marjanovic. I no 
made up the individual words, just but an adjective and a noun together. You 
got the meaning right off the bat, and that tells me the term worked in 
communicating what was needed. I could also have used "lumper mentality." More 
on "taste" below.

<if you went to meetings you'd see where this line of research is taking us: 
once you pull out the stratigraphic and ontogenetic signals, what you;re left 
with is the taxonomic signal. You can only make it work the other way round 
when you have a sample of 1 (when relative strat and ontogeny do not matter, or 
at least not as much). I understand that this is a new way of looking at 
taxonomy (or at least, mostly new to dinosaurs), but it yields advances in 
understanding that cannot be achieved through morphology alone.>

  I can understand this. I get stratigraphy, although you may not think I do. 
But our primary lens is through morphology. We do not toss morphology for the 
sake of stratigraphy, just as authors should not toss strat for morph (although 
this has been done: some authors have referred fossils to named forms on the 
sole reason due to implied stratigraphic position, ignoring morphology, or 
denouncing the morphology as relevent --- especially when it differed from the 
taxa to which they were referred). By the same token, ontogeny is only as good 
as the authors being absolutely sure that the morphology is consistent, the 
strat is consistent, and that they are not operating on a preconceived notion.


<"preconceived theory": so if you come up with a hypothesis first which you 
then propose to test, is this preconceived? do you actually understand how to 
conduct a scientific enquiry, or do you think every analysis starts out as a 
random data gathering that you hope to find some pattern in?>

  Preconceived conclusion? My bad. Preconceived hypothesis is what you have up 
there. Horner has argued, without formal testing, that declined diversity was 
absolute and prolonged in the Maastrichtian. I assume this places a bias on the 
argument. Note that I infer a consistent taxonomic label in the face of debate 
(like using *Ingenia* for any crestless oviraptorid) a "bias." Precluding the 
birds-aren't-dinosaurs hypothesis (or theory) is the same. Bias. Does Horner 
have this as strong as the "*T. rex* was a scavenger argument that he published 
in anything less than an informal layperson's book, but never backed up in a 
formal paper for longer than the biodiversity declination argument? I have no 
clue, but I would argue because of the duration and lack for formalization 
(which has prompted several authors to write papers refuting a never-published 
hypothesis) an "issue of bias." Refer to my first quote in my signature.


<You just don't get it. It's amazing. Maybe we couldn't tell to which species 
different Toro specimens belong to without further data.>

  This tells me that _you_ don't get "it." 

  I'm not talking about the morphology of a form that is recognized as 
"Torosaurus" versus "Triceratops" -- recognized largely from the issue of 
squamosal elongation, etc. I am talking about the _name_ *Torosaurus latus* 
which, as you may or may not know, is rooted on a HOLOTYPE SPECIMEN. To 
whichever taxon this specimen belongs, so too the name *latus* is attached. If 
this specimen belongs to a form that is NOT referrable to either a form that 
includes the HOLOTYPE of *prorsus* or the HOLOTYPE of *horridus,* then *latus* 
has a taxonomic identity than cannot be subsumed into either of them. 

  It is irrelevant (absolutely) whether "Torosaurus" is a synonym of 
"Triceratops" on its own. "Torosaurus" and "latus" are _two different taxa_ 
under the practice of Linnaean taxonomy (the system used to subsume them in 
Scannella and Horner). If *latus* (the only taxon at issue here!) is a synonym 
of either *prorsus* or *horridus*, it has NOT been published, and because of 
this, the formal synonymy of *Torosaurus* into *Triceratops* does not occur. 
If, instead, it is argued that the morphology comprising *Triceratops prorsus* 
and *Triceratops horridus* also includes *Torosaurus latus*, _THEN_ you may 
argue that (as no one has ever objected) that these taxa form a complex that 
may be called *Triceratops* (as three independant species), but may also be 
more inclusive (e.g., *Nedoceratops*, *Eotriceratops*, [Editaceratops]). You 
may note how none of this has ANYTHING to do with stratigraphy, just taxonomy.

  No matter how the morphology or the phylogeny falls, the nomenclature follows 
the rule of where the species goes, not the genus, even if we would be content 
to use both terms for the same thing. I could gain the same resolution, same 
stratigraphic arrangement, and same temporal breaks in the lineage by using a 
different name for each segment, even to make it look like a "genus" for each 
segment, so that *horridus* and *prorsus* each had their own "genus." None of 
this matters but for taste, unless a definition can be offered by which I may 
use to determine when and when not to use a "genus" name for a species. As none 
was provided by Scannella and Horner, I assume they, too, misunderstand this 
distinction, and thus the paper by which they used to sink *Torosaurus* does 
nothing of the sort until a paper is issued that sinks *latus* or shows that 
*latus* falls into a group better termed *Triceratops* (as a third species, a 
synonym, or whatever).

<You need ontogenetic and stratigraphic data. This comes FIRST, not last, and 
that's why the papers come in this order.>

  And you may then no longer wonder why I argued that the taxonomic structure 
should have waited! But it didn't. We are still waiting for the strat data 
which, as you said on Zach's blog, was going to show which species *latus* was 
a synonym of. Again "cart before the horse."


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