Re: Titanoceratops, giant ceratopsian from New Mexico

[Denver Fowler <df9465@yahoo.co.uk>]

----- Original Message ----
From: Jaime Headden <qi_leong@hotmail.com>

>  I haven't read Longrich's paper, and won't comment on it. 

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

>Your responses to said paper were in part due to the discussion on synonymy 
>with 
>
>ceratopsians, which lead to discussion of the argument about the ontogeny you 
>and others (i.e., Horner et al.) remark on (in various venues) avidly. 
>

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 
Titanoceratops.

> The paper has been criticised,[ ...]. I and other have commented on Horner's 
>long-held "belief" [...]-- that end-Cretaceous dinosaur diversity was 
>diminishing. When you assess this "belief" in connection with nomenclatural 
>practices increasing the recognition of named taxa in the Maastrichtian 
>relative 
>
>to the Campanian, one may get a sense that taxic reduction was _not_ so 
>marked, 

>if present at all. 
>

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.


 > Horner, Goodwin, Scannella and even Fowler may all be correct in the 
ontogenetic schemes presented, and the histological analysis showing late-onset 
"adult" morph in some of these taxa, but the question of the taxonomy which 
these authors have debated hangs on a taste issue that is not sub
and this includes the proposed but as yet unpublished 
stratigraphic argument which somehow (again, argued, pushed, but unpublished) 
supports taxic reductionism in ceratopsians.

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). 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. 


 > These are besides the point. The authors themselves admit large margins for 
disagreement when it comes to their theories of synonymies (Horner and Goodwin 
indicated that the morphological differences between *Pachycephalosaurus* and 
*Stygimoiloch* presented the largest room for debate in their proposal for 
synonymy, while Scannella and Horner dismissed the small-bodied "adult" morphs 
in their *Triceratops*/*Torosaurus* sample as "variation) 


Recognition of variation is the first step, understanding the origin and  
significance of that variation is the next step. It could be that the variation 
is pathologic, taphonomic, biogeographic, ontogenetic, stratigraphic, or 
individual variation within a species. Once you have ruled out all of these 
possibilities, you're left with either an unknown factor, or a genuinely 
different taxon. Or you can ignore these other possibilities and just call it a 
new taxon to begin with ("diversity first": 19th century science, and the 
reason 

why we had 16 species of triceratops, which didn;t help us understand anything 
much). Oversplitting only really helps to identify characters that vary. The 
source of
ss these in support of their -- again -- preconceived theory. 

"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? 




>Adding in the theory that stratigraphy can inform on taxonomy simply muddles 
>the 
>
>mixture, as biostratigraphy continues to to run rampant in some circles while 
>it 
>
>remains a statistical non-science.

Egads! Such ignorance!

>  The difficulty here is that this completely ignores how taxonomic 
> condensation 
>
>works. Simply having "Torosaurus is Triceratops" is meaningless without an 
>understanding that synonymy occurs in TWO different levels, and when only one 
>level is used, it leaves open the other option. 
>

You know... you should read Longrich's paper. you really should.

Current taxonomic practice has great difficulty dealing with morphology change 
through time. We're at a point where this is critical, because we have a sample 
of Triceratops (coupled with ontogenetic and strat data) that is about as large 
as exists for any dinosaur. Adherence to an archaic way of treating taxa is 
hindering our ability to understand them. The endless discussion of priority 
etc 

on this list does nothing to advance understanding. Indeed, it retards 
understanding of paleobiology by reducing down lineages (which are continuous 
through time) into discrete little packages that only work when time is a 
constant: in the fossil record it isn't. Even Hennig recognised this: he never 
intended systematics to be used on fossils because the inherent problems with 
the method create the very issues that get endlessly debated. And lets not get 
started on how systematics deals with stasis and non-stasis. taxonomy and 
systematics have great utility to a point, but we are now getting to the point 
where datasets are good enough that these previously reliable methods
only reason I have been dogged about this topic and this particular issue 

>is because ... I have yet to get a concrete response on this[...]. Instead, it 
>would be handled in a "future paper," which is idiotic: You do not argue a 
>synonymy, then state this synonymy will be explained later, and have that 
>original proposal "stick."

I disgaree with many people's research, but I wouldn't label them idiots. Read 
Longrich's paper, then I expect to see another endless stream of criticisms 
regarding his (proposed) sinkings without making species distinctions. Or you 
might just ignore it because you really only want to pick at the same boring 
criticisms of a few things that Jack wrote

> So, until the paper that formalized synonymy _at the species level_ is out, 
>*Torosaurus latus* will remain as likely and viable a name to use for *latus* 
>as 
>
>*Triceratops latus* or *Triceratops horridus* or whatever.

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. Maybe this happened 
because there are too many species already: oversplitting has a negative effect 
this way. If you saw Scannella's talk at SVP, you'll see why we have these 
taxonomic issues. For at least a little while, we're not going to see taxonomic 
stability for all historically described morphologies of Triceratops. We've got 
new specimens that are allowing us to decipher some of the described species 
(ie, why do they seem to have a mixture of traits), but all the ICZN monster 
manuals and latin/greek dictionaries in the world won't help you do this. You 
need ontogenetic and stratigraphic data. This comes FIRST, not last, and that's 
why the papers come in this order.