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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


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