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RE: Brrr, bone chilling paleopolar summers(Polar dinosaur growth and other new papers)



  While it is "fair" of Paul calling me out on my credentials for any reason 
based on what I said, it is "unfair" for Paul to throw the argument from 
authority in here. Not only is this a commonly supported logical fallacy, it is 
one Paul is using to appeal to those who agree with him in the general on the 
subject that because he's "done [X]," and I have not "done [X]" he matters 
more. This only matters on the subject of [X], however, not in the general, and 
this is where such a thesis fails and why it is a logical fallacy. This is not 
directed at Paul in the specific, but if he wants to argue that it is, and my 
disclaimer is some editing problem, that's his to do. I won't answer his 
appeals to my lack of authority in these cases except in specific contexts, 
which are below; however, I'd like to note that as a published author, Paul 
work has come under citation for its breadth, but many of the specifics he's 
written on have yet to be shown to be supported; his WaPo piece is not on 
anything to do with paleoclimatology or extinct animal behavior, and has 
nothing to do with this list, along with one of the websites he's asked me to 
go to, and has no relevance to this argument.

  In the specific things he notes, however, I have a few issues.

1. Relationship of the Campanian-Maastrichtian Prince Creek Formation:

Paul argues:
<However, the fossil record to the south has major time gaps in it, the Prince 
Creek Pachyrhinosaurus fauna is from a narrow time zone that apprently does not 
correspond with anything to the south, and we know that dinosaur species were 
turning over rapidly. It is probable that the Alaskan Pachyrhinosaurus is a 
distinct species that appeared later than P. canadensis which is later than P. 
lakustai. Since sediments in southwestern Canada contemporary to the Alaskan 
deposits and vice versa may not exist we are unlikely to be able to ever test 
how widely distributed the species in the region were.>

  Based on biostratigraphic calibration, the Prince Creek Fm has been linked 
from the late Campanian and is largely if not fully early Maastrichtian in age 
(Fiorillo et al., 2010). This equates it in age with the Horseshoe Canyon 
Formation in explicit age, and somewhat with the St. Mary River Formation. As 
you note, the sediments appear to mingle, if not interpolate, with the recovery 
of *Pachyrhinosaurus lakustai* (oldest), *Pachyrhinosaurus canadensis* 
(middle), Kikak–Tegoseak ?*Pachyrhinosaurus* (youngest). Similarly, with the 
narrow exception of *Alaskacephale gangloffi,* virtually no taxa from the 
Prince Creek Formation have been identified beyond the broad category of 
"genus," indicating that despite the recovery of massive amounts of bones from 
what are largely monotaxic bonebeds, specific identifications are wanting. In 
most cases, theropods are identified solely on the basis of teeth, and in many 
of them -- such as *Troodon* (Fiorillo & Gangloff, 2000; Fiorillo, 2008) -- 
this is based on the general habit of throwing specific elements into a general 
morphology, disregarding the improbable stratigraphic conundrum this creates 
when lumping taxa from the middle Campanian to the end of the Maastrichtian. 
I've discussed this habit at length before, it's on my blog in various spots, 
and I only need to reflect on the varying habits of taxonomists who lump and 
split taxa and how it is largely a "taste" issue and seldom a "science" issue.

http://qilong.wordpress.com/2011/03/14/taste-versus-science/

  This tells me further that reference of taxa made to "*Edmontosaurus* sp." et 
al. are not always done on the sense of an affirmative argument, but because 
they are the least problematic containers for the material pending further 
description, and that there's a tendency to place these bones there due to 
association to faunas further south.

2. Relative Climate of the Colville Basin

  When I wrote that the North Slope sediments, including the marine extension 
of the stratigraphy in the underlying Schrader Bluff Formation, were largely 
endemic, I did so generally on the basis of the Prince Creek Formation. I 
should note that all of the Prince Creek sediments are terrestrial and for the 
most part represent miring events and infills. They are all "freak accident" 
facies, as is common in floodplain facies. The marine reptiles we'd expect to 
find in the formation are likely not there because there are no marine reptiles 
in the preservation regime.

<[F]inding herps is easy via the teeth and scutes any population will leave 
behind in hard fossil bearing sediments (at J Farlow's Pliocence Pipe Creek 
site I helped screen in part by heroically hauling lots of sediment full 
buckets in June the main finding was turtle scutes).>

  I've gotten the impression so far that based solely on Paul's personal 
experience, he seems to think this should then be true for all geological 
sites. Isn't this another logical fallacy? Generalizing from the specific, you 
wish to infer that the absence of a finding means it will be found. While this 
inference is testable, he further states:

<It has over the decades become increasingly obvious and remarkable that the 
same North Slope Prince Creek sediments chock full of dinosaur bones and teeth 
including little dino, and some wee mammals, is just not producing herps 
despite the efforts of skilled field workers to test this unusual and important 
absence.>

  Paul should note that, with few exceptions, all Prince Creek sites are 
monotaxic infills (Fiorillo et al., 2010). Polytaxic assemblages like the Ghost 
Ranch *Coelophysis* bed have yielded very small numbers of non-theropod taxa, 
and yet recently, based on deliberative study, new taxa have recently been 
recorded, including an as-yet unpublished bizarrely prognathic basal theropod. 
similarly, other quarries known and sampled for other a century have yielded 
the ?silesaurid *Dromomeron roemeri* (Irmis et al., 2007), the Morrison 
Formation yielded new skeletal remains of the small reptile *Macelognathus 
vagans* (Göhlich et al., 2005), etc.

  Paul also seems to be extrapolating site-based comprehensive screening to 
formation-wide concentrations, but it should be noted that, among many other 
things, the Whitaker Quarry does not represent all of the Chinle Formation, the 
Brushy Basin Member is not the entirety of the Morrison (which is also yielding 
new large _sauropods_! Harris & Dodson, 2004).

  Paul is thus saying that the absence of evidence is evidence of absence. 

  This leads us into the idea that because of the lack of apparent "herps," the 
Prince Creek Formation simply lacked them. Paul makes other broad extensions on 
this, but most curiously the following:

<The paleoclimatological research based on multiple lines of evidence shows 
that even the summers did not provide enough ambient or direct solar heating to 
support terrestrial bradyenergtic ectotherms.>

  This does not mean that there weren't other types of "herps." But then, since 
Paul is using a typological term here to refer to a specific paraphyletic 
group, I am going to assume he is specifically referring to a particular 
grouping which has not developed any other non-bradymetabolic means of 
sustaining itself. Moreover, you constrain this sentence to "terrestrial ... 
ectotherms." Good show! Now you can't be wrong, even if a terrestrial croc or 
lizard were recovered, because it's not a "herp."

3. On Migration

<[M]arine organisms can and do migrate by simply drifting thousands of miles on 
the currents without expending any long distance travel energy. For that matter 
carcasses can drift for hundreds or thousands of miles, and countless dead 
marine reptiles must drifted into the arctic ocean from further south over the 
eons (likewise finding a dinosaur skeleton in deep water marine deposits does 
not tell us about that habitat).>

  So at this point, I will take the hint that Paul may be attempting to place 
the Alaskan chamsposaur there by _accident_, but also that "wandering" equals 
"migration." This is in the same context that Paul mentions caribou and 
wildebeest, known migrators. Do they never return back, making seasonal 
pilgrimages to and fro? I thought that was what we were talking about when 
infering that the North Slope was the northern extent of a migratory route? Did 
I miss something where we can now pretend some happenstance is just as likely 
to produce the effect we regard as migration because it does not conform to our 
previously held arguments? If the marine reptiles are not endemic to any degree 
or are not seasonal migrants, then they must be associated; but the same cannot 
be true for the terrestrial fauna, because it's so much harder to get them a 
few thousand miles distant. Why then cannot the latter imply the former was 
migratory? Because Paul is arguing that his energetic regime is true for the 
reptiles, and thus they could not be seasonal migrants:

<[T]he existence of marine reptiles in the Arctic Ocean sediments simply does 
not tell us anything about the situation in terms of land animal energetics up 
on the shore.>

  Paul's argument that reptilian metabolic and thermoregulatory capabilities 
does not exclude the likelihood of marine ectotherms migrating, and the 
presence of testudine and champsosaur fossils in the Late Cretaceous sediments 
of the Colville Basin casts doubt on whether they _could not_. Paul attempts to 
dismiss this by casting this material as floaters or "wanderers," or accidental 
corpses. The range of exceptions to migration being brought up, including the 
ludicrous amount of distance to bring otherwise southern Canadian taxa into the 
Arctic, stretches credulity. Paul's attempt to back this up uses the 
generalization fallacy, as though that could _prove_ anything.

  My argument remains stable:

A. If the *Pachyrhinosaurus* material represents a new taxon, it is a taxon 
unique to the region: it is endemic. This is true for the *Troodon* material as 
well, and is likely true for the scores of hadrosaur and other ornithischian 
material, and the theropod teeth collected. I am contradicted here only when 
these fossils are shown to not bear unique features to the exclusion of more 
southerly named taxa and it is not necessary to make those taxa paraphyletic in 
order to raise new taxonomy.

B. Migration can also interfere with my argument to endemism, as it would 
support that the taxa on the north side of the Brooks Range were able to cross 
it regularly and are part of a population south of it. It may be that the taxa 
south of the Range were distinct from those further south in Alberta/Montana, 
and thus support Alaskan endemism to the exclusion of North Slope endemsim.

  I have not argued that migration is occuring in either terrestrial or marine 
faunas, only that the faunas as preserved seem broad only in the context of 
taxonomic "level:" The higher you grade the taxa (i.e., further from "species") 
the more broadly the taxa will be able to be lumped, and thus be used to reject 
endemism without actually regarding it. Migration is possible and likely for 
various taxa, but I infer based on the taxic endemism that it was unlikely to 
be occuring terrestrially. I do not say it does not occur, and evidence may 
imply it does. This may not be as true in the marine, but if dinosaur bones are 
showing evidence for wintering in the same region as the one they summer in, 
then it implies a lack of even terrestrial migration.

Fiorillo, A. R. 2008. On the occurrence of exceptionally large teeth of 
*Troodon* (Dinosauria: Saurischia) from the Late Cretaceous of northern Alaska. 
_Palaios_ 23:322-328.
Fiorillo, A. R. & Gangloff, R. A. 2000. Theropod teeth from the Prince Creek 
Formation (Cretaceous) of northern Alaska, with speculations on arctic dinosaur 
paleoecology. _Journal of Vertebrate Paleontology_ 20(4):675-682.
Fiorillo, A. R., McCarthy, P. J., Flaig, P. P., Brandlen, E., Norton, D., 
Jacobs, L., Zippi, P. & Gangloff, R. A. 2010. Paleontology and 
paleoenvironmental interpretation of the Kikak–Tegoseak dinosaur quarry, 
(Prince Creek Formation: Late Cretaceous), northern Alaska: A 
multi-disciplinary study of an ancient high-latitude, ceratopsian dinosaur 
bonebed. pp.456-477 in Ryan, Chinner-Algeier & Eberth (eds.) _New Perspectives 
on Horned Dinosaurs: The Royal Tyrell Museum Ceratopsian Symposium._ Indiana 
University Press (Bloomington, Indiana, USA).
Göhlich, U. B., Chiappe, L. M., Clark, J. M. & Sues, H.-D. 2005. The systematic 
position of the Late Jurassic alleged dinosaur *Macelognathus* 
(Crocodylomorpha: Sphenosuchia). _Canadian Journal of Earth Sciences -- Revue 
canadienne de sciences de la Terre_ 402:307-321.
Harris, J. D. & Dodson, P. 2004. A new diplodocoid sauropod dinosaur from the 
Upper Jurassic Morrison Formation of Montana, USA. _Acta Palaeontologica 
Polonica_ 49(2):197–210.
Irmis, R. B., Nesbitt, S. J., Padian, K., Smith, N. D., Turner, A. H., Woody, 
D. & Downs, A. 2007. A Late Triassic dinosauromorph assemblage from New Mexico 
and the rise of dinosaurs. _Science_ 317:358–361.

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)


----------------------------------------
> Date: Mon, 8 Aug 2011 19:51:33 -0400
> From: GSP1954@aol.com
> To: dinosaur@usc.edu
> Subject: Re: Brrr, bone chilling paleopolar summers(Polar dinosaur growth and 
> other new papers)
>
> It can be frustrating responding to J Headden because it is not always
> clear what he is saying. In any case.
>
> Alaskan dinosaur distribution -
>
> JH seems to be saying that the North Slope Alaskan Prince Creek Formation
> fauna was endemic because it is distinct from faunas further south. However,
> the fossil record to the south has major time gaps in it, the Prince Creek
> Pachyrhinosaurus fauna is from a narrow time zone that apprently does not
> correspond with anything to the south, and we know that dinosaur species were
> turning over rapidly. It is probable that the Alaskan Pachyrhinosaurus is a
> distinct species that appeared later than P. canadensis which is later than
> P. lakustai. Since sediments in southwestern Canada contemporary to the
> Alaskan deposits and vice versa may not exist we are unlikely to be able to 
> ever
> test how widely distributed the species in the region were. (A similar
> situation occurs with the supposed northern Triceratops versus southern
> "Torosaurus" faunas, the latter is actually earlier so we do not know how far 
> south
> the Triceratops fauna actually extended. And the southern fragmentary
> Torosaurus are not the lower Hell Creek Lance Torosaurus which was just old T.
> horridus anyhew.) So it looks like we are stuck holding our paleogeographic 
> bag
> on this one. Darn.
>
> Lack of Alaskan L Cret land herps -
>
> As I can attest have been on a fair amount of Mesozoic and Cenozoic
> sediments, finding herps is easy via the teeth and scutes any population will 
> leave
> behind in hard fossil bearing sediments (at J Farlow's Pliocence Pipe Creek
> site I helped screen in part by heroically hauling lots of sediment full
> buckets in June the main finding was turtle scutes). Even many polar sites
> have produced bradyenergetic reptile bits and pieces, that's one way we can
> tell they were on occasion warm enough to support such ectotherms. It has over
> the decades become increasingly obvious and remarkable that the same North
> Slope Prince Creek sediments chock full of dinosaur bones and teeth including
> little dino, and some wee mammals, is just not producing herps despite the
> efforts of skilled field workers to test this unusual and important absence.
> The absence continues to be documented in the recent literature. The
> paleoclimatological research based on multiple lines of evidence shows that 
> even
> the summers did not provide enough ambient or direct solar heating to support
> terrestrial bradyenergtic ectotherms. The evidence is therefore
> overwhelming in favor of the Prince Creek climate being unable to support low 
> metabolic
> rate land animals at any time of the year, and that will remain so until
> the unlikely event that herps start showing up in signficiant numbers.
>
> Marine herps --
>
> JH wrote that
> << The presence of marine reptiles is _relevant_ because they are reptiles,
> and as such lacked specific metabolic elements to handle harsher polar
> winters. Your inference here, then, is that marine reptiles migrated, which
> would imply they have a similar metabolic constraint and allowance as marine
> mammals do which also migrate. At that point, you need to back this statement
> up with evidence, else is remain rhetoric. >>
>
> Again moi does not quite get what point JH is trying to make concerning
> polar marine reptlies contemporary with the Prince Creek dinosaurs. In any 
> case
> they certainly are irrelevant to the issues I brought up about
> dinoenergetics for a bunch of reasons. Depending on the streamlining, 
> swimming costs
> 6-12 times less than walking the same distance, so even bradyaerobic swimmers
> easily cross entire oceans with ease, while not even tachyaerobic walkers
> move anywhere nearly as far in straight travel lines (even caribou and
> wildebeest actually circle around in limited areas). Also, marine organisms 
> can and
> do migrate by simply drifting thousands of miles on the currents without
> expending any long distance travel energy. For that matter carcasses can drift
> for hundreds or thousands of miles, and countless dead marine reptiles must
> drifted into the arctic ocean from further south over the eons (likewise
> finding a dinosaur skeleton in deep water marine deposits does not tell us
> about that habitat). And because swimming is so energy cheap, low metabolic 
> rate
> animals can be pretty active even in very cold waters, such as basking
> sharks (whose core temps have been measured as hardly above cold water temps)
> and Greenland sharks. Of course recent papers suggest many Mesozoic reptiles
> had elevated metabolisms. Nor did the ocean water get below freezing as often
> happened on shore where winter blizzards occurred regularly. So the
> existence of marine reptiles in the Arctic Ocean sediments simply does not 
> tell us
> anything about the situation in terms of land animal energetics up on the
> shore.
>
> Whay JH is saying is annoying not only because it is badly edited, but
> because he is making demands upon others like me he is not qualified to make. 
> As
> per "At that point, [GSP] need to back this statement up with evidence,
> else is remain rhetoric." That demand reveals that JH, who does not contribute
> to the technical literature, is not familiar with the technical literature,
> including my extensive contributions. I have already repeatedly explained
> how and why marine animals tell us very little about the energetics of land
> animals in academic papers, so there is no need for me to meet JH's demands
> that I have to do so here or my assertions are mere rhetoric. Instead JH needs
> to become intimately familiar with the literature before commenting on the
> work of those who are active in the field. I -- well actually my ace web
> site operator -- have gone to considerable effort to post just abut all my
> papers at www.gspauldino.com. In the future before being critical of my
> statements JH needs to first check my papers and see if I have already 
> addressed the
> issue.
>
> Since I published one of the most widely read Washington Post opeds this
> spring, I have been receiving critical e-mails. My policy has been to respond
> once, pointing out that the emailer apparently is being critical without
> first reading my extensive research on religious sociology and theology 
> (www.gsp
> aulscienceofreligion.com). I tell them that I will respond to a second
> message only if they make it apparent that they have gone to the time and
> trouble to respect my efforts by first actually reading what I have said in 
> the
> literature.
>
> Likewise, if JH (and others who are not practicing paleontologists) want to
> debate and dispute with those who publish in the technical literature, then
> he needs to be first read the latter. In many cases he might find his
> concerns answered. If not he is more than free to voice his concerns and pose
> questions, of course in a manner respectful of those more qualified than he
> is. (Note that since JH tried to tell me what I needed to do, I get to do the
> same in reverse.)
>
> GSPaul
>
>
> </HTML>