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Re: BADD BCF
In a message dated 95-12-02 17:28:51 EST, longrich@phoenix.Princeton.EDU
(Nicholas R. Longrich) writes:
>This could also be interpreted as the idea that large predators
>tended to evolve from the small theropods, rather than from other large
>predators. Big animals, I am guessing, do pretty well in relatively
>stable situations, while small animals clean up when things go haywire.
>Big animals go extinct more easily, possibly (look at the last ice age),
>just because A) there are fewer of them B) because there are fewer of
>them, the number of different genes they might have would be different
>C)they take longer to reproduce, so evolution cannot procede as quickly
>amng elephants as, say, mice which can run through a couple generations
>per year. Of course, big animals have a lot of advantages too. They can
>be very efficient, migrate huge distances, and eat low quality food.
>The general impression I often seem to get from land animals is
>that small animals evolve into big animals and more small animals, then
>the big animals go extinct (repeat as necessary). Anyways, just some
>vague thoughts on the subject.
I go into this a bit in one of the introductory sections (on dinosaur
diversity and extinction) in MM #2. Your vague thoughts are not as vague as