Re: Hibernating Dinosaurs?

[Tim Williams <twilliams_alpha@hotmail.com>]

John Bois wrote:

> Hibernation is one of the main proposed mechanisms for mammal survival at
> the K/T.

It is?  Who says?

> So, obviously, since no non-avian dinosaurs survived, none could
> have hibernated!  Except for those important hibernators, birds, of
> course.

Let's say an extraterrestrial impact did happen circa 65 million years ago.  
I think we can say that the resulting havoc on the Earth's ecosystems 
(terrestrial and aquatic/marine) would have been profound.  Generalist 
feeders might have held an advantage over specialists, especially if the 
former were small in size.  I don't think that there is any reason to 
believe that the ability to hibernate or not was the deciding factor.

As for the Australian/Antarctic dinosaur thing raised by Kris.  There is no 
direct evidence of hibernation (or aestivation) in Australo-Antarctican 
dinosaurs.  However, since a large chunk of this combined mega-continent lay 
within the Antarctic Circle, any dinosaurs (and we know they lived here 
during the Cretaceous) would have had to contend with very cool, very long 
and very dark polar winters.  This has led to speculation that if any 
non-avian dinosaurs survived the K/T extinction, they may have lived Down 
Under.

I've nothing about a hibernating ornithomimid (unless someone suggested that 
_Timimus_ hibernated).  The large eyes of _Leallynasaura_ have been regarded 
as an adaptation to seeing in the dark; but it could just as equally be a 
juvenile trait.


Tim


> On Wed, 16 Mar 2005 MariusRomanus@aol.com wrote:
>
> > What's the current opinion about the idea of hibernating dinosaurs from
> > Australia/Antarctica? The only thing I can find is mention of a possible
> > hibernating ornithomimid, but I can't find any substantial reasons that 
> support the
> > claim.
> >
> > Thank ya much.
> >
> > Kris
> >
> > http://hometown.aol.com/saurierlagen/Paleo-Photography.html
> >