Brain expansion (Evolution)

by David Turell , Tuesday, July 28, 2020, 19:02 (1577 days ago) @ dhw

DAVID: What happened to 'forced by a new idea'.

dhw: “Forced” is your word, not mine, but in any case my comment above is a response to your claim that my theory is inconsistent with sapiens history. I have shown you that it is not.

Your changed theory is consistent, but previously you said an earlier-brained homo had an idea, which idea in order to be implemented had to demand an enlarged brain that naturally appeared:

"Yes, the larger brain would have required more feeding. Yes, once the brain had expanded, it would have been able to design and develop more intelligent and efficient tools. How does this invalidate the proposal that each expansion was triggered by a new concept from the smaller brain? How does it prove that developing and making the FIRST artefacts could not have been the cause of the expansion?" From April (2020-04-04, 14:06)

Quite clear to me and the long stasis in sapiens does not support it .

DAVID : We see both much shrinkage and slight growth, but overall the extra cells were discarded after the brain was carefully reconstituted as specialized networks to fit the uses humans found for it, with final overall shrinkage.

dhw: “Carefully reconstituted”? Sapiens started off with a brain that contained 150 cc of cells that were never used again, and so when he started to implement his new ideas through enhanced complexification, the unnecessary cells disappeared. That doesn’t mean the entire brain was carefully taken apart and put together again in a different form, and it still doesn’t tell us why your God gave us more cells than we needed.

Your assumption that the extra neurons were never used, is not my theory. My point is that many of them were used in the plastic reorganization of our brain to fit our new uses and needs. I assume old and new neurons were discarded as unnecessary after the reorganization.

dhw: Once again: my theory is that ALL the enlargements were caused by new requirements that could only be met by additional cells. NOBODY knows what these requirements were! But all expansions, including our own, were followed by periods of stasis, when there were no new ideas that required any further changes! Modern science confirms that the brain changes in response to new requirements and not beforehand. So what theory have I abandoned?

You have never explained the idea that if a new idea drove brain expansion why the long stasis before implementation in the new brain. I view the drive of a new idea should have continues into an immediate action by the new-sized brain. But it doesn't.