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Re: Torosaurus NOT Triceratops



You should probably make it amazingly clear what I'm really pretty sure you 
actually mean - that by miscode what you really mean is that in their work they 
made choices that others might/would interpret differently in coding these 
characters, perhaps because they (the characters that is) need much more data 
or study and/or may be really tough to interpret/code. You are not saying they 
chose to do so on purpose. We've had odd times in the past where a few 
individuals seemed to casually suggest people misrepresented data on purpose 
and that, of course, without massive proof is reprehensible. I presume you mean 
the former and not the latter but correct me if I'm wrong.

Ralph


-----Original Message-----
>From: Paul P <turtlecroc@yahoo.com>
>Sent: Mar 1, 2012 1:41 PM
>To: dinosaur@usc.edu, Michael.OSullivan@port.ac.uk
>Subject: Re: Torosaurus NOT Triceratops
>
>--- On Thu, 3/1/12, David Marjanovic <david.marjanovic@gmx.at> wrote:
>
>> > Am I the only one who thinks that the dataset used for the determination
>> > of Torosaurus as a valid genus, or something synonymous with
>> > Triceratops, is capable of being used to support either view...
>> 
>> Yes. It's not who analyses the data, but whether enough
>> methods are used.
>
>Um, actually, no. The data in this paper can be used to 
>argue that they're separate taxa OR to argue that Toro. is 
>Triceratops, just like you can pretty much show anything 
>you want using many published character matrices. All you 
>have to do is miscode one or two key characters for one 
>or two key specimens. Note the asterisks in Longrich and 
>Field's table. Statistically, i think that table/data 
>shows that Torosaurus *is* Triceratops just as much as 
>it shows the opposite. The more immature specimens are 
>skewed toward Triceratops while the most mature are skewed 
>toward Toro. I know that doesn't prove anything, but it's 
>statistical. 
>
>My hunch is that Torosaurus is valid, at least *some* 
>Toros. In the end they may all prove to be synonymous, 
>but what about those Toros in UT? Just a sampling issue? 
>And what about immature chars in some Toro skulls? John 
>Scannella and the MOR group have tried to address that 
>using histology, but the dataset is still incomplete. 
>As Denver says (i think), it's unfortunate that many of 
>the older but well preserved skulls don't have detailed 
>stratigraphic data with them, but they are still useful. 
>They're not just heads floating in space or whatever. 
>
>All dinosaurs are morphotaxa (er, all *extinct* dinos), 
>so sample size is crucial. There is a lot of circularity 
>in trying to separate individual variation from ontogeny 
>from taxonomy from dimorphism in similar taxa. You can 
>apply the tools, but in the end, it's largely statistical. 
>I think in a year or two you will see someone arguing 
>that Toro is the mature form only of *male* Trikes. 
>Despite Horner and Padian on dimorphism, that seems to 
>me a more likely 
>-- On Wed, 2/29/12, Michael OSullivan <Michael.OSullivan@port.ac.uk> wrote:
>
>> From: Michael OSullivan <Michael.OSullivan@port.ac.uk>
>> Subject: Re: Torosaurus NOT Triceratops
>> To: bcreisler@gmail.com, dinosaur@usc.edu
>> Date: Wednesday, February 29, 2012, 6:45 PM
>>
>> Am I the only one who thinks that the dataset used for the determination
>> of Torosaurus as a valid genus, or something synonymous with
>> Triceratops, is capable of being used to support either view, depending
>> on who's analysing the data. I think there's a real danger of
>> subjectivity obscuring the reality. Whatever the hell that is...this
>> rate, Torosaurus will be revealed to be a late living Stegosaur
>> ---
>> 
>> Michael O'Sullivan
>> 
>> Palaeobiology Research Group
>> Postgraduate Student
>> School of Earth & Environmental Sciences
>> Burnaby Building
>> Burnaby Road
>> Portsmouth
>> PO1 3QL
>> 
>> Email:michael.osullivan@port.ac.uk
>> >>> Ben Creisler  01/03/12 12:10 AM
>> >>>
>> From: Ben Creisler
>> bcreisler@gmail.com
>> 
>> 
>> A new paper in PLoS ONE:
>> 
>> 
>> Longrich,  N.R. & Field, D.J. (2012)
>> Torosaurus Is Not Triceratops: Ontogeny in Chasmosaurine
>> Ceratopsids as a Case Study in Dinosaur Taxonomy.
>> PLoS ONE 7(2): e32623.
>> doi:10.1371/journal.pone.0032623
>> http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0032623
>> 
>


Ralph E. Chapman
Paleontologist & Technologist
New Mexico Virtualization
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