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Re: Brrr, bone chilling paleopolar summers(Polar dinosaur growth and other new papers)
In a message dated 8/12/11 7:42:17 PM, firstname.lastname@example.org writes:
<< I'll check into that. It doesn't sound right, however. There was a
when all the continents were in one place, and it wasn't both the north and
the south pole.
> On Mon, Aug 8th, 2011 at 11:52 AM, Dora Smith <email@example.com>
>> Has everyone forgotten that the continents were not located where they
>> now? The arctic could not have supported dinosaurs when it wasn't frozen
>> over, since there is no dry land there. Antarctica was not always as the
>> south pole and was once warm.
> During the Cretaceous, the North American plate was further north (closer
> to the Arctic circle),
> and Australia was further south (closer to the Antarctic circle).
> As far as I know, Antarctica has always been close to the south pole. It
> has wandered about a bit,
> but it has been in the general vicinity for a long time.
> Dann Pigdon
So, who is right hear. Dora who seems the think the continents were all
joined together in the Late Cretaceous versus Dann who thinks that the
Australia he lives on was close to the South Pole back in the day. I know, I'll
check the paleomaps conveniently reproduced in the Princeton Field Guide to
Dinosaurs that I can't over recommend you all get if you haven't already, it's
great (albeit perturbingly dated what with the pace of dino research these
days). Well, this is interesting. Seems that the supercontinent was starting
to break up all the way back in the Jurassic, and Alaska even then was close
to the Santa Claus land, and Australia to the other pole. This remains true
as the continents move. By the L Cret the continents are already fairly
close to where they are today, with the Arctic Ocean not too different from
today. But the pole appears to have been closer to the Bering region then, so
Alaska was probably closer to the pole. Australia, however, was much further
south than it currently is, so it was considerably closer to the southern
pole at the time. Antarctica was at the southern axis of rotation.
So Dann, and all the researchers who work on polar dinosaur question, are