Re: Antarctic Elasmosaur

["Steve Brusatte" <dinoland@lycos.com>]

On Thu, 28 Feb 2002 06:17:48  
 Dann Pigdon wrote:
>Steve Brusatte wrote:
>
>>Perhaps...or, maybe they seasonally migrated (like some modern whales, which 
>>are endothermic, but that's beyond the point).  It's only speculation, though.
>
>Except that whales only migrate to breed in warmer waters. Plesiosaurs
>and Pliosaurs in southern Australia (inside the Antarctic circle in the
>Cretaceous) appear to have bred in the colder waters.

True.  So, perhaps the elasmosaurs had no trouble living within the colder 
waters.  Why does every organism that inhabits colder environments or waters 
automatically have to be endothermic?  As Rutger mentioned, the environment 
within the Antarctic circle during the Cretaceous was, although still cold, 
much more temperate.  The really nice fern specimens William Hammer has brought 
back from the _Cryolophosaurus_ site manifest this.  And, as Rutger said, 
animals such as elasmosaurs and mosasaurs weren't very closely related to the 
dinosaur/avian stock.  Perhaps they evolved endothermy or another type of 
elevated metabolism separately, but maybe the new elasmosaurs could live and 
breed in the colder waters just fine.

Steve

---
***************************************************************
Steve Brusatte-DINO LAND PALEONTOLOGY
SITE: http://www.geocities.com/stegob
ONLINE CLUB: http://clubs.yahoo.com/clubs/thedinolanddinosaurdigsite
WEBRING: http://www.geocities.com/stegob/dlwr.html
INTERNATIONAL LANGUAGE SITE: http://www.geocities.com/stegob/international.html
****************************************************************



2,000,000,000 Web Pages--you only need 1. Save time with My Lycos.
http://my.lycos.com