Evolution and humans: all over Africa (Evolution)

by David Turell , Saturday, April 28, 2018, 16:02 (2399 days ago) @ dhw

dhw: Wow, here we have a possible catalyst! All this time, you have been asking why it took so long for sapiens to use his new capacity. I pointed out that all pre-sapiens stages have involved long periods of stasis, and it was not until the new geniuses came along that the brain had to expand. But it didn’t occur to me that the sapiens stasis might have ended because of a change in the climate. So 12,000 years ago, new environmental conditions allowed a vast range of new possibilities for the sapiens brain to exploit. It also fits in perfectly with my evolutionary hypothesis that advances are caused by the drive for survival and the exploitation of new opportunities provided by environmental change. Many thanks for this vital piece of information!
DAVID: We couldn't do much during an ice age. I've
been saying we lived survival lives until until recently. Survival life is not civilized life. […]

dhw: I know. And for months you have been asking why sapiens didn’t use his great brain for two or three hundred thousand years, until approx. 12,000 years ago. Now you have an answer: the climate changed. Rejoice!

It wan't all ice for 315,000 years. The ice ages came and went. If the last pre-sapiens had concepts that demanded brain enlargement (your 'push' theory) they should have been able to use it during the 'nice' climate periods. We were given a bigger brain and had to learn how to use it. Your parents gave you a two-wheeler and you had to learn to balance on it. Same concept.