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Re: paleontolgist, dinosaur
From: Jeff Poling <email@example.com>
> This is the first time I've seen this hypothesis. I doubt it's true.
> The first known flying bird is mid Jurassic, some 75 million years before
> the K/T event. Recent fossil finds show that birds were widespread and
> diverse by the early Cretaceous at the latest ... yet pterosaurs survived
> right up to the big figurative boom.
True, they survived, but apparently at *greatly* reduced diversity.
Only about three families of large "Pteranodon"-like forms are known
from the entire Late Cretaceous. This is compared to the enormous
variety of smaller pterodactyloid and rhamphorhyncoid pterosaurs
known from the Late Jurassic. And I know of only one or two families
from the Maastrichtian (the one containing Quetzalcoatlus, and perhaps
the one containing "Titanopteryx", if that is distinct). Indeed I
only know of a small handful of *genera* in the Maastrichtian.
Thus, the idea is that by the middle of the Cretaceous most of the
*smaller* flying niches were occupied by birds. Thus only a a few
individual extinctions were needed to finish off the pterosaurs,
unlike the still diverse dinosaurs.
The peace of God be with you.