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> You'd also have to consider the fact that something that would affect
> some dinosaurs would have no effect on others (similar to modern
> diseases in various populations of animals today). The Black Plague
> doesn't seem to do much to rats that carry the fleas...
Actually, not true. Rats are also killed by the plague-causing bacterium
_Yersinia pestis_. During the Black Plague, the urban rat population of
Europe was being killed off at a rapid rate due to _Yersinia_ infection.
It's only because its natural host was declining that the rat flea resorted
to biting other mammals - including humans - and therefore passed the
bacteria on to them. Rats are not the natural host for the palgue
bacterium; they were victims too (though it's hard to feel sorry for them.)
If rats didn't succumb to the bacteria, then we may not have had the Black
> The most popular non-dinosaurian reptiles to go extinct were the marine
> reptiles: the plesiosaurs and the mosasaurs.
And which were the most *unpopular* non-dinosaurian reptiles? :-)
> In the air, pterosaurs were another large group to disappear. On an
> interesting (if not entirely arguable) note, crocodilians, lizards,
> snakes, turtles, mammals and birds seemed to have come through the
> extinction pretty well.
I don't think 'pretty well' is entirely accurate. These groups certainly
survived, and placentals/eutherians seem to have been much less affected
than other groups. But many reptile (apart from dinosaurs), mammal and
avian groups were decimated at the K/T boundary, or went extinct altogether.
I don't think we know enough about the late K neornithine record to gauge
how they responded to the K/T event.
Timothy J. Williams, Ph.D.
Iowa State University
Ames IA 50014
Phone: 515 294 9233
Fax: 515 294 9359