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Re: Large last gasp of pterosaurs
--- Graydon <oak@uniserve.com> wrote:
>
> There are, to my mind, four serious problems with invoking 'competition
> with birds'.
>
> 1) we don't have any evidence for it, no strata where the pterosaurs
> give way to shore birds, frex.
Why "shore birds"?
> The few mixed communities we have
> evidence for have way more pterosaurs than birds. (7 Archeopteryx
> versus how many pterosaurs?)
These are also the earliest definite avialan fossils, so it's possibly that
this new clade hadn't established a large foothold yet.
What about Liaoning? There are far more birds than pterosaurs.
It's interesting that today's two large clades of flying animals (_Neornithes_
and _Chiroptera_) largely avoid competition by being awake at different times.
Then again, it doesn't seem that pterosaurs or early avialans had any nocturnal
adaptations....
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