Brain expansion: different theories about rapid expansion (Evolution)

by dhw, Saturday, September 26, 2020, 11:46 (1301 days ago) @ David Turell

DAVID: We don't know at which stage of brain size the hippocampus was given the ability to add cells. We only know what happens now. God provided the extra cells for complexification in this brain and while it reorganized it shrunk. You can imagine anything else you wish to.

dhw: Since we only know what happens now, and we know that the brain cells autonomously complexify and even add new cells in response to new requirements, it is absurd to reject the possibility that the same thing happened in former times.

DAVID: Blithely stating 'adding new cells in response to new requirements' while ignoring that the only cells we can add are to help the hippocampus with memory storage, i.e., is twisting what we know to aid you theory. Our oversized brain added cells to heavily used areas as it shrunk.

The hippocampus proves that the brain can add cells where needed. That is not twisting anything. It is evidence of the feasibility of the argument that earlier expansions entailed adding cells where needed.

dhw: I asked you for proven instances, and all you can come up with is a repetition of your unproven theory that your God enlarged the brain in anticipation of the hominin producing new artefacts, whereas my theory is that the hominin’s brain expanded through the process of producing new artefacts! By contrast with your theory, I have the proven example of the modern brain, which changes IN RESPONSE to new requirements and not in anticipation of them.

DAVID: Same reversed twist. Our enlarged brain responded to new requirements and reorganized only after a long stasis period when it was not used differently than in the past and then it shrank as the new neurons were used.

dhw: There is no reverse twist. We are discussing the possible cause of expansion, which I propose was a RESPONSE to unknown new requirements. Thank you for confirming the known fact that brains do reorganize themselves in RESPONSE to new requirements. You complained that my theory is unproven, so I asked you for proven instances of the brain altering its structure BEFORE new cells are required. You couldn’t, whereas I have proven instances of the brain changing IN RESPONSE to new requirements. And yet again: post-expansion stasis (resulting from the fact that there were no new requirements) and shrinkage (because efficient complexification made certain cells redundant) are irrelevant to the question of WHAT MADE BRAINS EXPAND. Please stick to the point.

DAVID: I'm exactly on point as you twist facts to fit our natural theory. OUR brains do 'reorganize' using the extra cells they started with.

Yes, that is the current complexification, i.e. post-expansion. Our subject is why the pre-sapiens brain and other brains expanded, i.e. added to their quantity of cells.

DAVID: What haven't I proven. please deal only with what we know and then theorize if you wish.

That is precisely what I have done. We know that approx. 315,000 years ago the brain expanded. We know that the modern brain changes in response to new requirements. We know that it has stopped expanding and complexification has taken over. We know that it shrunk, and we agree that this was because of the efficiency of complexification, which made certain cells redundant. However, we know that the hippocampus produced additional cells, and it is reasonable to assume that these were required. You have agreed that this process would have taken place without your God’s intervention. Out of these facts and your own agreements, I theorize that in the days when brains and skulls expanded, cells were added to other parts of the brain when needed, and this happened in the same way and for the same reason as cells are added to the hippocampus. Meanwhile, you have no answer to my bold:

DAVID: Of course I couldn't answer your bold. God enlarges and prepares each new stage for new mental developments. The last part of the bold is a truism. Our brain does respond to new requirements. It was set up to do so by God.

So if our brain responds to new requirements, why do you insist that earlier brains changed BEFORE there were any new requirements? What happened to: “please deal with what we know and then theorize if you wish”? But yes, I would say that ALL brains respond(ed) to new requirements, and if God exists, then of course he set them up to do so. He would have invented the mechanism that gave them this ability! No further involvement required. Why is this not feasible?

I have switched the section on “errors” to the appropriate thread.