>> As for the "3 million years", not being "overnight", Gould has noted
>> that "The human brain is now about three times larger than that of
>> Australopithecus" and that "This increase has often been called the
>> most rapid and most important event in the history of evolution."
>> (Gould S.J., "Ever Since Darwin", Penguin, 1977, p183)
I'll accept that it was fairly quick as evolutionary events go, but 3
million years doesn't appear supernaturally rapid to me.
It may be that other events of similar magnitude were just as fast, but
occurred so long ago that the fossil record isn't finely sampled enough
to document it, e.g. the evolution of whales. There are some
transitional whale fossils, but it's not nearly as complete as the
hominid fossil record.
>> I would be interested in any plausible purely naturalistic causal
>> explanation of both each "single stage" and especially "the whole
>> sequence", with particular respect to its unprecedented rapidity.
There have been any number of "just so" stories: hunting hypotheses,
food-sharing hypotheses, etc. The problem is disproving them, not
finding them!
>> Also, as to "No single stage" looking "particularly difficult",
>> Eiseley's point was that seemingly retrograde steps had to occur
>> before the brain expanded, eg. "Childhood had to be lengthened...We
>> lost our hairy covering, our jaws and teeth were reduced in size, our
>> sex life was postponed, our infancy became among the most helpless of
>> any of the animals ..." (Eiseley L., "The Immense Journey", Victor
>> Gollancz: London, 1958 p122-123).
Maybe some context is missing from that quote, but nothing Eiseley says
there states that those steps had to happen before the brain expanded.
If he did say it, he was wrong. Example: going from A.africanus to
H.habilis to H.erectus to H.heidelbergensis to H.sapiens, there is a
steady decrease in the size of the molars, and a steady increase in
brain size.
>> I fail to see how becoming "among the most helpless of any of the
>> animals" conferred a selective advantage *before* the human brain had
>> grown large enough to compensate by enabling higher intelligence.
Who says that we became helpless *before* brain size increased?
-- Jim Foley Symbios Logic, Fort CollinsJim.Foley@symbios.com (303) 223-5100 x9765* 1st 1.11 #4955 * "I am Homer of Borg! Prepare to be...OOooooo! Donuts!!!"