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Re: late night thoughts: misunderstand what?
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Datum: Thu, 14 Jun 2007 09:17:37 -0700 (PDT)
Von: don ohmes <firstname.lastname@example.org>
Whew... all of a sudden some kind of dam breaks and 40 messages flood me...
Just so much now:
> As to the record, I would like to see a plot of known sauros, body size
> vs time.
You will see one when I get my M. Sc. thesis published. It's not a matter of
simple plotting, because you have to take the phylogeny into account (size is
after all heritable).
Results so far: No size increase (or decrease) for sauropods, or even for
sauropodomorphs as a whole. And no, I did not take *Magyarosaurus* into account
(I thought it was juvenile -- only one species of it is, apparently).
> There are two mechanisms here; predation driven size increase, and the
> case where the prey, for whatever reason, can no longer increase their
> size (ie, 'predators won').
Oh, that's what you mean by "predators won". I'd have thought when there's an
arms race and the predators win, the prey dies out because the predators are
too successful; on the other hand, if the prey wins, the predators must either
switch to some other food or die out.
As for why sauropods are so big in the first place, that may have any number of
reasons. A prime candidate is the fact that the bigger you are, the longer you
can afford fermenting food in your gut, which in turn means that you can live
off poor-quality food (such as conifer needles). If you're just big enough, you
have an unlimited food source and no competition.
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