Evolution and humans: caves and jewelry (Evolution)

by dhw, Friday, May 11, 2018, 11:59 (2386 days ago) @ David Turell

DAVID’s comment: More evidence of little use of our big brain for a very long time after its arrival.My interpretation is it took time to learn to use it.

dhw: To repeat: As with all stages of human evolution, there were long periods of stasis once the brain had expanded. Not a matter of “learning to use the new brain”. What is being learned if there has been no progress? It needs geniuses to come up with new ideas, or major changes in the environment to either necessitate new ways of thinking or provide new opportunities.

DAVID: At each stage, whether in small groups like hunter-gatherer, or larger settlements as farming appeared, humans learned to depend upon each other and different people took different cooperative roles to play. But it still took 305,000 years for this to happen, and all the while before farming, the brain sat in survival mode.

I really don’t think it took 305,000 years for humans to depend on each other and take different roles! It took a long time for sapiens to make the leap which led to civilisation as we know it. Each stage of brain enlargement brought with it leaps that were major at the time, no matter how minor they may seem to you now: use of tools, weapons, fire, cooking, clothes etc., generally connected with improving the chances of survival and then followed by long periods of stasis. Whatever leap caused the final brain enlargement followed the same pattern. Then, as you say:

DAVID: Then the use of the brain exploded in exponential terms. It was waiting there for us to use.

Yes, it needed the geniuses, or the major climate change 12000 years ago to which you drew our attention, to spark the explosion.

DAVID: There is no evidence of prior conceptual pressure causing enlargement, for the new concepts from habilis to sapiens were not very different 315,000 years ago. Habilis survival, sapiens survival. No evidence of thinking pressure to enlarge.

See above for concepts. Enlargement happened! You keep telling us that your God did it (what is your evidence?) because otherwise pre-sapiens couldn't think up his new concepts, so I don’t know why you are now belittling the new concepts. I propose that implementation of the new concepts caused the expansion, just as the sapiens brain changes through complexification and limited expansion as a result of implementing new concepts.