Dear Andrew;-
Good answer. Only one question: Are you sure the brain is our most
specialized organ? If it is, why can't we figure out how to push a "chad" all
the way through the hole?
Art
"Andrew K. Rindsberg" wrote:
> Peter Egerton had it right the first time: The five digits are a very old
> trait, dating back to the early amphibians. Most vertebrates have developed
> other numbers of digits by mutation, e.g., the occasional human mutation for
> six digits. But a few vertebrate groups have maintained this ancient trait
> to the present day.
>
> It may be odd to think of humans as "primitive" when we pride ourselves on
> being the pinnacle of creation. The fact is that many of our traits are
> relatively unchanged and unspecialized, and this, coupled with high
> intelligence, turns out to be a very effective tool kit for survival. Our
> feet and hands are not all that different from the original amphibian feet,
> as a look at any salamander will show. Our forefeet have not become wings,
> as in birds and bats and pterodactyls. Five-fingered hands can climb trees,
> pick up and throw objects, or even convey language. Neither cats nor horses
> can do most of these things; they are far more specialized than we are.
> Think of how specialized these animals are in diet and habitat: anteaters,
> tree sloths, rhinoceroses, pandas, beavers, panthers, crocodiles, ostriches.
> Yet all made of the same stuff, and all with an ancestor that had five
> digits on each limb. The brain is our most specialized organ.
>
> Andrew K. Rindsberg
> Geological Survey of Alabama
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