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Re: Large last gasp of pterosaurs



Jaime A. Headden wrote:
> The collected and
> observed trend would lend credence to an idea that birds were filling the
> small flier niches, and pterosaurs dominated the large fliers. But there
> does not seem to be a marked increase in large birds known that would have
> removed the azhdarchids and pteranodontids from the picture,

Exactly as would be expected from the way they each provided the energy
to maintain level flight, and the ways they carried their respective
structural loadings.

> So I don't think the evidence currently favors
> pterosaur/bird competition to explain absence of diversity in either
> group, or the forced extinction of one or some groups.

I could be persauded to drink to that.  You wouldn't even have to twist
my arm.

> One could easily
> attempt to use this diversity through the Cretaceous as a means to explain
> enantiornithine extinction, as much as pterosaur extinction, prior to the
> K/T event.

Agreed.  But I don't think there is sufficient fossil record to draw any
real conclusion either way.

Jim