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RE: Dinosaurs to birds
At 03:44 PM 1/22/99 -0800, Stewart, Dwight wrote:
> @@@@@@@@@@@@@@@@@@@@@@@@@@@@
>
> But, still, why did THOSE particular large vertebrates survive?
>Individual cases of luck, where
> one particular specimen survives, yet not another; I can understand.
>But, why were non avian
> dinosaurs, plesiosaurs, etc. so globally unlucky?
Perhaps they tended to be less likely to be in protected sites?
Perhaps it was just blind luck.
Perhaps they were already at reduced population levels.
> Luck, by
>definition should be totally random & governed by the laws of statistical
>chance. The KT extinction was massive, but why did some animals & plants
>cross the boundary in large numbers, but others completely vanished?
Can you demonstrate that the distribution of survivors and non-survivors
*wasn't* random? If by chance all, or all but a few isolated individuals,
of a species were killed, that would eliminate the species.
Mind, I do not think it was wholly random. Larger animals seem to have
been less likely to make it through than smaller ones, for instance. Since
most non-avian dinosaurs of the Maastrichtian were larger than most birds,
this may be enough to explain the difference.
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May the peace of God be with you. sarima@ix.netcom.com