Re: erect posture and its implications

[Human <100533.1710@compuserve.com>]

> On Thu, 18 Jun 1998, Larry Dunn wrote:
> 
> > How does this follow?  The only migrating terrestrial animals I can
> > think of (off the top of my head) are herbivores.  Are there
> > terrestrial migrators that are insectivores?  Carnivores?  
> 
> Hi Larry!  Long time, no read.  Wolves will follow caribou herds on
> their migrations in Alaska, and I believe that they once followed
herds of
> bison on the plains.  This last may be incorrect and, at any rate,
it's
> basically the same thing as the former.  

Agreed, but are they then migrating to exploit various stationary food
sources?  

Aren't they just migrating because their food source is migrating? 
That's not the kind of migration that the person I replied to (the
enigmatic "Human") was referring to.

Hi there, I am the enigmatic "Human" (my family  name is Human)....

I vaguely imagined that it would be advantageous for herbivores to follow
their migrating food source (that's why they migrate as far as I know;
seasonal changes force them to follow vegetation so you can say their food
is always "migrating" away from them.......I kind of imagined a scenario
such as continental drift = climate changes = seasonal  vegetation changes
= need to follow = survival of animals equiped to do so = more pressure on
animals not equipped to do so and increasing adaptation for those surviving
migrators (increasingly economical locomotion, efficient circulation and
temperature control) . Once endothermy is established, if coupled with
insulation = ability to exploit small animal niches formerly closed to
non-insulated non-endtothermic animals (ie, birds get to occupy the warm
blooded small animal niche unavailable to their uninsulated endothermic
dinosaur cousins, but can only  occupy those niches not occupied by the
early mammals (ie the air).  

Now I am aware that the reasoning is probably woolly, even I can point to 
animals that seem to bely this reasoning,  but I would have  been suprised
if it was so simple. It's just resonable "how about this for size"
supposition by a complete novice in the field.

cheers, martin human
Larry
http://members.tripod.com/~megalania/index.html

_________________________________________________________
DO YOU YAHOO!?
Get your free @yahoo.com address at http://mail.yahoo.com

<