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RE: Horner's Pachy Lumpin' - Your Thoughts?



Denver Fowler wrote:

>Feel free to push away from your computer desk and aid in the hunt for
>more fossils, or make a donation to your local museum. For us, this past
>year was fairly productive for pachys, and we failed to find anything that
>falsified the ontogeny hypothesis. I spend over three months of every year
>digging up more specimens, or running up and down hills measuring
>stratigraphic position so that we can reanalyse old hypotheses, rather than
>just criticise.

Ooouuuch. That's one hearty slap in the face to people who live in regions with 
absolutely *no* fossils to aid in hunting for, and who don't have any free cash 
to either travel to an area that does have fossils or to donate to their "local 
museum". (And not everyone has a "local museum".)

Christopher Collinson wrote:

>Sorry Michael but the important parts of that skull, i.e the squamosals,
>perietals, frontals, dome, spikes, etc are all real. Only the face and
>snout are reconstructed.

Okie dokie then. It's real. That's fine. But I actually don't see any more than 
three squamosal horns in that picture anyway.

Here are some more photos of the same:

http://upload.wikimedia.org/wikipedia/commons/b/be/Museum_f%C3%BCr_Naturkunde_Berlin._Fossil_Stygimoloch_spinifer_002.jpg

http://z.about.com/d/dinosaurs/1/0/z/-/-/-/stygimoloch.jpg

http://bestiarium.kryptozoologie.net/wp-content/uploads/2009/07/Stygimoloch-spinifer-Sch%C3%A4del-3-1024x768.jpg

http://bestiarium.kryptozoologie.net/wp-content/uploads/2009/07/Stygimoloch-spinifer-Sch%C3%A4del-2-1024x768.jpg

All I'm seeing are the three hypotrophied squamosal horns, surrounded by bony 
nodes. Where is this fourth squamosal horn? Does anybody else see it?

>I find it most interesting that you are so quick to make ad hominem
>attacks against Horner and Goodwin, where its only actual flaw is that it
>sinks a nomen Bakker, when just a few weeks ago you were lambasting
>everyone for rightfully dismissing the steaming pile of crap that is Gong
>et al 2009.

Okay, the record needs to be set straight. First, I have never made any ad 
hominem attacks against Horner or Goodwin (nor have I seen anyone else do so). 
I like both of them, and probably agree with Horner on more issues (other than 
this one) than you think. If you consider an ad hominem attack to be pointing 
out that rigor is not Horner's strong point, and that he often neglects and 
ignores important data when forming his hypotheses (just *look* at his _T. rex_ 
publications to discover the truth in these statements), then your definition 
of an ad hominem "attack" is an interesting one indeed. I am merely pointing 
these things out, and I am not dismissing the Draco = Stygi = Pachy hypothesis 
based solely on Horner's record - i. e. What would be a *real* ad hominem 
attack.

Saying that "its only actual flaw is that it sinks a nomen Bakker" implies 
(rather explicitly) that I disagree with Horner simply because I don't want to 
see a taxon named by Bakker sunk. Perhaps that was percisely your intention, I 
do not know. But the truth of the matter is that I could care less who named 
the stupid thing, and I would gleefully watch _Dracorex_ (and _Stygimoloch_ 
while we're at it) sink into the Canyon of the Invalid Taxa if I believed that 
that's what the evidence required. Being a Bakker fan has nothing to do with 
anything, as I am a Horner fan as well. (And a Goodwin fan, for that matter.) 
This has nothing to do favoring certain paleontologists over others and 
everything to do with science. That you believe otherwise reveals that you 
don't understand this situation, and that rather than learn the real facts you 
would rather just assume things to be happening that are, in fact, not 
happening at all.

As for Gong et al. 2009, I never "lambasted" anyone. Disagreeing with folks and 
lambasting them are two different things. I never attacked anyone for 
dismissing the paper, I merely shared my views, which is what I thought the DML 
was for. I never once stated anything aggressive or rude or lambasting toward 
anyone who disagreed with me regarding the Gong et al. paper. (I also have 
never referred to the published work of others as "steaming piles of crap". I 
don't consider Horner & Goodwin 2009 or the opinions expressed therein to be a 
"steaming pile of crap", even though I disagree with their hypothesis.)

Tim Williams wrote:

>Overall, as others have said, I think the best way (in fact, in a
>scientific sense, the *only* way) to refute Horner &c's hypothesis is to
>assemble data that supports an alternative hypothesis

First I'd like to see strong data assembled that supports *their* hypothesis. 
I'm with Ralph in that I find it odd how Horner's hypothesis, still in its 
early stages and in need of a lot more testing, etc. is being taken as The Real 
Truth and the burden is considered to have swiftly and automatically shifted to 
other models. I actually am of the opinion that the burden does not always 
necessarily lie with the new and "out-there" claim, however it does when the 
case made in its favor is as weak as it has been. Like it or not the burden of 
proof is still on Horner at this stage to demonstrate to us that the limited 
data we currently have really shows what he says it shows, not on those who 
happen to be skeptical of his latest radical claim.

~ Michael


----------------------------------------
> Date: Sat, 9 Jan 2010 14:17:38 -0800
> From: thats_mr_annoying_to_you@yahoo.com
> To: tehdinomahn@live.com
> CC: dinosaur@usc.edu
> Subject: RE: Horner's Pachy Lumpin' - Your Thoughts?
>
>
>
> --- On Sat, 1/9/10, Michael Erickson wrote:
>
>> From: Michael Erickson
>> Subject: RE: Horner's Pachy Lumpin' - Your Thoughts?
>> To: "Dino List"
>> Received: Saturday, January 9, 2010, 9:03 AM
>>
>
>>>http://upload.wikimedia.org/wikipedia/commons/8/84/Museum_f%C3%BCr_Naturkunde_Berlin._Fossil_Stygimoloch_spinifer_003.jpg
>>
>> That skull is not real. It is heavily reconstructed - it
>> bears almost no resemblance to the few complete
>> (unfortunately undescribed) _Stygimoloch_ skulls that are
>> known. And if you take a look at this Wikipedia article:
>>
>
>
> Sorry Michael but the important parts of that skull, i.e the squamosals 
> perietals, frontals, dome, spikes, etc are all real. Only the face and snout 
> are reconstructed. It happens to be a Triebold reconstruction based on a 
> privately owned specimen represented by the cast seen here:
>
> http://www.angelfire.com/mi/dinosaurs/images/casts/stygimoloch_1.jpg
>
>
> I find it most interesting that you are so quick to make ad hominem attacks 
> against Horner and Goodwin, where its only actual flaw is that it sinks a 
> nomen Bakker, when just a few weeks ago you were lambasting everyone for 
> rightfully dismissing the steaming pile of crap that is Gong et al 2009.
>
> Christopher Collinson
>
>
----------------------------------------
> Date: Sat, 9 Jan 2010 18:03:44 +0000
> From: df9465@yahoo.co.uk
> To: dinosaur@usc.edu
> Subject: Re: Horner's Pachy Lumpin' - Your Thoughts?
>
>
>
> M. Erickson said:
>
>>[some editing] ... the burden of proof still lies with Horner - because well, 
>>let's face it, his hypothesis is extremely bizarre and counter-intuitive
>
> I don't see why the hypothesis is extremely bizarre, nor counter-intuitive. 
> Besides, these are not scientific terms. Despite the outraged protestations 
> here that this is something exceptional, resorption and severe remodelling of 
> cranial ornament late in ontogeny is seen in many ceratopsian clades (which, 
> as marginocephalia, are the most closely related clade to pachys).
>
> Histology is still a somewhat abstract discipline, and is barely
> understood or considered by the majority of dinosaur workers. I think that 
> you would
> find that even dinosaur histologists like horner, padian, erickson et
> al, would admit that we are still only beginning to understand how to
> interpret bone histology. However, the histological evidence, as we currently 
> understand it, shows that these horns are remodelling.
>
> What I take from Horner & Goodwin, and the two talks presented at SVP that 
> supported this work (which included a talk by Sullivan, a coauthor on the 
> description of Dracorex) is that the dome develops through ontogeny. 
> Flat-headed pachys are immature individuals. Dracorex is therefore, very 
> likely not to be exhibiting adult morphology. I would not be surprised if 
> there were as many as 3 definable pachycephalosaurini taxa within the Hell 
> Creek, but I sincerely doubt that there were any more than one at any time. 
> To test this hypothesis we need not only new specimens, but quality data to 
> go with those specimens. You seem to think that there is no evidence at all 
> to support the hypothesis presented by Horner & Goodwin. As it stands, the 
> case for Dracorex simply being an immature Stygi is very strong. The case for 
> separating Stygi and Pachy is more of a judgement call, open to either 
> interpretation, depending on your inclination.
>
>
>
>> and is going to take heaps more evidence, especially *MORE FOSSILS* (can't 
>> emphasize that one enough), to demonstrate beyond reason
>
>
> Feel free to push away from your computer desk and aid in the hunt for
> more fossils, or make a donation to your local museum. For us, this past year
> was fairly productive for pachys, and we failed to find anything that
> falsified the ontogeny hypothesis. I spend over three months of every year 
> digging up more specimens, or running up and down hills measuring 
> stratigraphic position so that we can reanalyse old hypotheses, rather than 
> just criticise.
>
> Anyway, I fail to see why "diversity first" is any better a hypothesis than 
> "maybe they're ontogenetic". At least people who work on ontogeny actually 
> consider the diversity hypothesis. I don't see much of that happening the 
> other way round.
>
>> That is why, among other things, I was dismayed to see Longrich et al. 
>> applying Horner's still-highly-controversial hypothesis to other taxa as if 
>> it had already been validated(!?!?)..
>
> It has been published, so it can be discussed. It can be accepted by people 
> who write their own papers if they so feel. You might recall that it is 
> generally impossible to prove anything in a historical science, only to 
> falsify.
>
>
>
>
----------------------------------------
> Date: Sat, 9 Jan 2010 19:09:37 -0800
> From: tijawi@yahoo.com
> To: dinosaur@usc.edu
> CC: tehdinomahn@live.com; tijawi@yahoo.com
> Subject: RE: Horner's Pachy Lumpin' - Your Thoughts?
>
>
>
> Michael Erickson wrote:
>
>
>> The structures (pachycephalosaur horns and
>> ceratopsian epoccipitals) are not even homologous. Rather,
>> we have numerous examples, from both extant and extinct
>> taxa, that demonstrate that horn reversal during ontogeny is
>> not at all normal or natural for any terrestrial tetrapod.
>> We can even use the _Triceratops_ analogy as evidence
>> *against* Horner's proposals, for although the brow and
>> nasal horns of _Triceratops_ change shape significantly
>> during ontogeny, there are no reversals or reabsorbtions. In
>> terms of size, the horns just keep getting bigger and bigger
>> until they are at their longest and largest in fully grown
>> adults."
>
>
> Well, not exactly. Horner &c argue that that there is a resorptive 
> contribution to this change of shape ("eroded as they reduced 
> dorsoventrally"). This is why I quoted their text. You may or may not accept 
> their interpretation. But, whether 'eppocipitals' and 'horn cores' are 
> homologous is largely irrelevant, because Horner &c at least offer a 
> precedent for the *principle* of the resorption of osseous tissue during 
> ontogeny.
>
>
> Overall, as others have said, I think the best way (in fact, in a scientific 
> sense, the *only* way) to refute Horner &c's hypothesis is to assemble data 
> that supports an alternative hypothesis. Simply accusing a hypothesis of 
> being "counter-intuitive" serves no purpose at all, and only produces more 
> heat than light. To switch to a well-worn argument, how many times has an 
> terrestrial/cursorial ("ground-up") origin of flight been crititized as being 
> "counter-intuitive"? It's not a valid scientific argument, and never has been.
>
>
> Cheers
>
> Tim
>
>
>
>                                         
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