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Re: Long, long last gasp.



>...given that most pterosaurs were apparently quadrupedal and many of
them would probably have had a bird like metabolism, being trapped on the
ground for even a few days could wipe out a species (especially if there
were other pressures).

Not if this species were wide ranging, and could wait it out on a remote
island somewhere.  Would a local event kill all albatrosses.  Or, are the
skies and ground perturbed globally in such a way that birds survive and
pterosaurs don't.

>Think of the advantage the heavily insolated running bird has in hunting
on the ground compared to a pterosaurs delicate quadrupedal movement.

I think this supports my contention that  birds could handle themselves
much better on the ground than pterosaurs (not that Jonas is arguing
against that).  By the way, how fantastic is it that some terrestrial
birds are immune to the world's nastiest, fastest predators.  Ostriches
foil predators that gazelles cannot.

__________________________________________________________

To clarify my point, is: An animal that relied on flight to catch its food
and would be ineffective at hunting on the ground (as most large pterosaurs
almost shurely were); This combined with a high active-flying metabolism and
bad weather (causing an enormous increase in calory requirements); That if
these conditions lasted long enough over a large enough area; it could have
very detrimental effects on the viability of most of the individuals in a
specie, even to extinction in some cases.

So I am making the assumtion that all flying animals could have been
grounded in most places for a few days, and pointing out the advantages in
relative size of wings and maneuverability of birds on the ground.

The important question here is would there have been enough bad weather
after the K-T event to cause this world wide, and the answer is probably no.

I will also point out that over the water or at even a relatively low
altitude weather is unpredictable and the average temperature is often just
a couple of degrees above zero. If you consider the heat loss to wind caused
in flight it seems unthinkable for these animals not to be able to handle
cold bad conditions.

The ocean even in the Cretaceous was not a bathtube
-Jonas Weselake-George