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

----- Original Message -----

> From: Jaime Headden <qi_leong@hotmail.com>
> To: Greg Paul <gsp1954@aol.com>; Dinosaur Mailing List <dinosaur@usc.edu>; 
> Jason <pristichampsus@yahoo.com>
> Cc: 
> Sent: Sunday, 7 August 2011 1:47 AM
> Subject: RE: Brrr, bone chilling paleopolar summers(Polar dinosaur growth and 
> other new papers)
>   Before we lose ourselves in the war of "you haven't done [X]" it 
> should be noted that no sedimentary regime is _ever_ fully sampled, 
> regardless 
> of how long it has been sampled. For example, and this one's just off the 
> top of my head, the Morrison and Dinosaur Park Formations have been sampled 
> for 
> well over a century and are STILL producing essentially new material 
> providing 
> new data on otherwise unknown portions of animals. Some of these are new 
> taxa. 
> Some of them MAY be new taxa. Claiming that the North Slope has been so 
> well-sampled that it cannot be said to produce new material of otherwise 
> unknown 
> bradymetabolic or ectothermal animals is to claim that we know everything 
> about 
> it that can be known (like how a pachycephalosaur was only very recently 
> named 
> from said sediments, cementing the idea that the formational regime is 
> similar 
> enough to that in southern Alberta we could surmise other Campanian Albertan 
> clades may be known in it).
>   So the statement "misleading misstatement" is neither, and it is 
> foolish to say it is.


In relation to this I'd like to point out that non-dinosaurian reptile fossils 
have been found in the North Slope of Alaska (Parrish 1987), but at a lower 
level in the Campanian when the average temperature was warmer (assuming one is 
comfortable calling 10°C "warm"). Yet despite "decades of sieving" the North 
Slope we still only have one fossil to show for it (a rather crappy mold of a 
partial turtle shell). This might suggest that -- contra Clemens (1992) -- 
there might be a taphonomic bias present. 

Regardless I'd say the North Slope still has plenty o
Parrish, J.M., Parrish, J.T., Hutchison, J.H. and Spicer, RA., 1987. Late 
Cretaceous vertebrate fossils from the North Slope of Alaska and implications 
for dinosaur ecology. Palaios, v. 2, pp. 377-389

Clemens, W.A. 1992. Continental Vertebrates from the Late Cretaceous of the 
North Slope, Alaska. ICAM Proc. 395-398