Brain expansion: different theories about rapid expansion (Evolution)

by David Turell , Monday, September 28, 2020, 18:05 (1515 days ago) @ dhw

dhw: All compartments of the brain consist of cells. If the cells in one compartment are able to add to their numbers in order to meet new requirements, why do you assume that the cells in other compartments could never have done the same at a time when expansion was possible? No, it’s not proven. Nor is your own divine dabbling theory proven. But why is my theory not feasible?

DAVID: It is not feasible because our brain is given a very specific neuron addition mechanism. It was thought for many years we didn't add neurons as adults. This is a recent very specific finding. If you believe in common descent, our current brain mimics the past which means the mechanism is very limited to one specific area all through evolutionary history.

dhw: Nobody knows why earlier brains added neurons. The modern brain is capable of adding neurons when necessary. It is perfectly feasible, then, that earlier brains also added neurons when necessary. The fact that the modern brain has ceased to expand, and now complexifies in order to meet new requirements, does not mean that the mechanism for expansion in the past only applied to the hippocampus!

If one believes in common descent, new advances must mirror past processes. For me our brain acts as old brains did. Which means new neurons added only to the hippocampus. Your thought is just wishful thinking.

DAVID: You can talk all around the stasis period but it is there and it tells me God prepares in advance for future use as He conducts advances in evolution. Your 'unknown new requirements' are unknown because there is not any evidence of them. 'Little was done with it' is stasis. You make my point while struggling with the issue.

dhw: I don’t know why you go on and on about stasis, which is irrelevant to the question of what caused expansion, and which is no problem at all for me but presents a big problem for you! Yet again: NOBODY knows what caused the expansion. I don’t suppose there are many scientists, though, who would announce that God must have stepped in one night and performed an operation on the brains, skulls and pelvises of a group of sleeping Moroccans. And so to stasis. My proposal: 1) brain expanded by meeting unknown requirement. 2) No new requirements for 280,000 years. No change in brain. That means STASIS. 3) New requirements after 280,000 years coincide with changes to the brain. You can hardly have a clearer, more logical sequence. Your belief: 1) God performs operation on Moroccans. 2) Moroccans do nothing with new brain for 280,000 years. QUESTION: Why would God expand brain 280,000 years before it was needed? Answer: to “learn how to use it” but “little was done with it”. Sorry, but I don’t think I’m the one who is “struggling with the issue”.

All depends upon point of view. I start with God running the show and my theory follows easily from that decision. You are searching vainly for a natural cause of brain enlargement, asana God. Your 'unknown requirement' is pure invention. All pre-Homo sapiens species fossils are aged with new artifacts, but not us!!! Fact, not imagination.