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Re: more dinosaur extinction stuff

On Mon, 1 Aug 1994, Stan Friesen wrote:

>  >...  Instead of why did the dinosaurs go extinct I wondered why
>  > did the mammals, lizards, fish, birds etc survive the same calamity?
> It is fairly simple, really.  In all of the big extinctions,
> generalists and opportunists do well, specialists do poorly.
> Also, large animals do poorly, and small ones do better. (This
> is actually a special case of the above, as large animals are
> almost always specialists in one way or another).

It is true that mammals, lizards, turtles, alligators, crocodiles, birds,
etc. did survive...but all those groups took quite a pounding also..
I believe I read somewhere that almost 60-80% of all life was effected.
I agree that generalists and opportunists do well against calamity. 
Dinosaurs at the end of the mesozoic were definitely specialized...maybe
to specialized.  A lot of work is still needed to prove this.!!

(Birds are specialized/highly evolved dinosaurs....so not all of them died!!!)

---John Schneiderman <dino@cwis.unomaha.edu>