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Re: The birds vs. the pterosaurs



> >It reminds me of a scene from Walking With Dinosaurs, when a plesiosaur
(or
> >was it a mosasaur--I don't remember) reached up and captured a theropod.
> >Thus, this aquatic animal was clearly at the top of the terrestrial food
> >chain.  Actually, I didn't like that hypothesis at all.

Neither did I. The theropod was *Allosaurus*, and the plesiosaur was
supposed to be *Liopleurodon*, which was ONLY 12 or so and not 25 m long as
claimed.

> I think it was some type of mosasaur, and it`s attack, (if it could have
> happened at all), was an unusual event. Hardly what would qualify placing
it
> at the top of a terrestrial food chain.It seems that the large pterosaurs
in
> question were specifically adapted for skimming the surface, and catching
> fish on a regular basis, thus qualifying their placement as top predators
in
> this particular food chain. PS,...I don`t believe a food chain has to be
> constrained to specific physical boundaries, ie...aquatic vs terestrial or
> airborn.

True. BTW, I'd call azhdarchids aerial, not terrestrial, as they seem to
have spent most of their lives hanging in the air above oceans, like
albatrosses.

> >Back to pterosaurs.  I figured the pterosaurs that survived to the end of
> >the Cretaceous, which were flying eaters of fish and therefore dependent
on
> >sight for finding food, simply couldn't see anything to catch in an
> >environment where the brightest light intensity was only a fraction of
that
> >of the full moon.
>
> Could have been. I was even going to mention this, but again, I think the
> root cause of the KT extinction was the short term (couple of months)
> depletion of the photosynthetic base of the food chain. That alone would
> account for the extinction of some forms, and the survival of others. This
> is seen as > the main cause < of the extinctions in the oceans, so why
> should terrestrial extinctions at the K-T boundary have some other
cause???

The impact was so catastrophic that it is quite useless to look for the
exact cause of the extinction of any group (and the fossil record will
hardly tell months apart).