Brain Expansion (Evolution)

by dhw, Sunday, May 10, 2020, 11:57 (1656 days ago) @ David Turell

dhw: I am asking for a logical reason why, if brain changes are known to be caused by “hard thinking” now, they could not also have been changed by “hard thinking” then. I am focusing on the process of thought changing the brain, not on comparing the forms of change.

DAVID: You are simply insisting without any logical thought extending from the facts we know that hard thought expanded brains up to 200 cc at a time. What we know is evolution builds upon past processes as organism complexify. It is reasonable, as I've stated, to assume that ancient brains did do some complexification with tiny areas enlarging and perhaps with some shrinkage as in ours. That makes more sense.

The logical thought concerns the one word you constantly avoid. If brains CHANGE through hard thinking now, why would they not CHANGE through hard thinking in the past? Then they needed to expand. Now they only need to complexify.

dhw: Shrinkage is irrelevant, as are the past 35,000 years, to the question of WHY brains expanded! How can shrinkage be caused by expansion anyway? We agreed that the efficiency of complexification made part of the brain redundant. Stop dodging the point that our brains CHANGE IN RESPONSE TO "HARD THINKING"!

DAVID: I'm not avoiding your inventions. The evidence we have is, as we learned use our big new brain by hard thinking, is that it shrank. You want to ignore that major point to championing that our tiny areas of enlargement must lead to a wild theory that hard thinking can expand brains by 200 cc.

It seems that the message will never get through. You agreed that shrinkage was due to the efficiency of complexification, and it is not the tiny areas of enlargement that I refer to but the process whereby "hard thinking" CHANGES the brain.

DAVID: You've just admitted the process in our brain occurs under an advanced complexification process and I've pointed out previous brains may have had simple versions of the same process as evolutionary theory would imply. Therefore I can accept that ancient brains may have had tiny expansion areas as ours does. That is consistent thought.

But it does not explain why ancient brains expanded! Hence the theory I am proposing.

DAVID: […] Proof???

dhw: What proof have you for your own theory that your God dabbled or preprogrammed all the expansions before they were needed?
DAVID: I have full faith and belief there is a designer who enlarged brain. I have no belief in chance causes which you are consistently trying to find.

My theory does not involve chance at all, and allows for God as the designer of the mechanism for brain change. Do you believe that your God complexified the relevant areas of the modern brain before people learned to read, memorize maps or play instruments? Or did he design the mechanism enabling the brain to respond to their “hard thinking” by complexifying itself? If you favour the second explanation, why do you think it illogical for the same God-designed mechanism to have enabled the brain to respond to “hard thinking” by expanding itself?

Transferred from “dualism”:
dhw: each successive expansion was caused by “hard thinking”, leading to increased knowledge and skills. Erectus was more advanced than australopithecus. We are more advanced than erectus. And so of course the increased knowledge and skills coincide with the bigger or vastly more complex brain (complexification having replaced expansion).

DAVID: In the bold I don't understand the use of the word 'coincide'. The larger brain allowed the development of our very advanced concepts, such as grammatical language 50-70,000 years ago, while erectus had very simple communication skills, and we didn't come out of erectus' stone age until 10-12,000 years ago. I view the stasis as proof we were given a brain we didn't know how use and had to learn to use it.

“Coincide” in the sense that the two go together, but as with the artefacts, I am proposing that it was not the larger brain that allowed our advanced concepts; it was our effort to give material expression to more advanced concepts that caused the brain and other related organs to change - the same process we observe today, when the brain changes in response to new tasks. As I was not around at the time, I can’t tell you what “big idea” would have expanded erectus’s brain to sapiens size, but the process of expansion followed by stasis was common to all our ancestors and in many cases for far longer than 280,000 years. I don’t know either why your all-powerful God would have given us a bigger brain before we needed it, or what you mean by we “had to learn to use it”. We’ve discussed that before. How did we learn to use the brain if we didn’t actually produce anything new for 280,000 years? It makes far more sense to me that the brain would have expanded because of a particular new need, and then life went on virtually unchanged (as for previous homos) until the next “big idea” required new uses of the brain. Immediately after expansion this would not have been anywhere near as complex as it is now, because "hard thinking" is what complexified it, and the efficiency of all the new complexifications is what made it shrink.