Re: Archaeopteryx and Flight

[ornstn@hookup.net (Ronald Orenstein)]

>The point is, why did the flycatching pterosaurs die out? That
>life style is quite viable still, and has been since about the
>Carboniferous.  it is not as if all pterosurs were in one lineage.
>Just because the Pteranodontid and Dsungapterid lineages shifted
>to fish eating and scavenging respectively is no reason for the
>Pterodactylid lineage to die out!
>

My question is: how can we be so sure this happened?  Flycatching pterosaurs
(or birds) are likely to be small, delicate and forest-dwelling, and our
fossil record of whatever occupied this particular niche may be very spotty,
dependent on specialized conditions such as those at Solnhofen.  The
best-known Cretaceous fossil birds were fish-eaters too (the hesperornithids
and ichthyornithids).  I realize that Sereno and others are now finding
smaller terrestrial Cretaceous fossil birds like Sinornis, but can we be
sure that pterosaur ecological equivalents to pterosaurs like Anurognathus
(say) were truly absent?
--
Ronald I. Orenstein                           Phone: (905) 820-7886 (home)
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