Brain expansion (Evolution)

by David Turell , Saturday, August 01, 2020, 14:02 (1364 days ago) @ dhw

DAVID: We do not know the length of time the Moroccan sapiens had been around, when the artifacts were made of or thought of. I agree artifacts are a factor.

dhw: So your reference [...] to the Moroccans does not in any way contradict my theory.

DAVID: It is neutral, not support.

dhw: Precisely. So there is no point in harping on about the Moroccans as if somehow their story contradicted my theory.

David’s second post deals with more finds relating to tools, which further confuses the issue of who did what when.

DAVID: I expected you to be confused. It was clear in that post that advanced stone tools predated Moroccan sapiens. The true confusion is no homo fossils to tell us who thought of it. No support for your theory a bright idea drives expansion to a new brain, which is why you have perfunctorily sloughed off the post.

dhw: I didn’t slough it off! On the contrary I presented it because it squashed your effort to use the Moroccans as evidence against my theory! Once more: NOBODY knows why the brain expanded. None of these articles provide the slightest support for your theory that one night God stepped in and dabbled with the brains, skulls and pelvises of a few Moroccans! Does that lead you to reject it?

I'll stick with a past comment:

DAVID: We can agree that bigger brains are consistent with better made tools. What caused the bigger brains is our dispute. I'll stick with God running evolution.

Note this article shows in tool making in a lesser brain by H. habilis:

https://science.sciencemag.org/content/369/6503/520.4?utm_campaign=ec_sci_2020-07-30&am...

A very rare type of tool made from a hippopotamus bone has been discovered at the Konso Formation in southern Ethiopia. This artifact represents a technological breakthrough achieved 1.75 million years ago. Bone is tricky to shape and requires considerable judgment and skill to form successfully. Sano et al. show how this large (>10 centimeter) fragment was intentionally shaped by a controlled knapping technique and turned into a handaxe. This breakthrough represents a step-change from the conservative thinking of previous tool makers. By analyzing the scarring around the edges of the superbly preserved tool, the authors inferred that the maker, probably Homo erectus, was able to adjust the thickness on both sides of the material by a distinctive flaking technique. This allowed it to be used for precise purposes, such as butchering animal carcasses. (my bold)

Comment: The Moroccan tools were not that advanced in comparison. Itty-bitty advances until very recently. The tools did not drive expansion. The bigger brains allowed the souls to develop new ideas.

DAVID: (on “Our unusual cerebellum”): This adds more to the amazing expansion of the sapiens brain. Unfortunately we cannot study pre-sapiens cerabellums to understand the evolution, but its ties to the expanded cerebrum could be newly arrived to aide in cognition and abstractions.

dhw: I’d be happy with “newly expanded cerebrum” rather than “expanded cerebrum newly arrived”. A dualist, in my view, would have to argue that all the complexifications and expansions were in RESPONSE to the soul’s new ideas. A materialist would argue that they caused the new ideas.

You are not my dualist,as my dualism is so different, as you well know.

DAVID: (on “Astrocytes drove enlargements): Our big brain is astroglial driven. "Due to an exaptation". Wow!: exaptations are unexpected changes in function of that which previously existed with a different function. As if God stepped in and added His design. It certainly was 'punctuated equilibrium', although not in the true Gouldian sense. One senses the appearance of a surprising evolutionary event.

dhw: Since there was a long period of stasis before, presumably, different parts of the brain changed their functions, and there were also long periods of stasis between earlier expansions, I reckon “punctuated equilibrium” is a good description. I don’t know why your God would have had to step in, since you have already agreed that complexification is an autonomous process. I would suggest that once major expansion had been discounted for anatomical reasons – part of my theory - intelligent cells (we shouldn’t forget that astrocytes are cells) cooperated in adapting themselves to perform whatever functions were required of them.

So confused!! 'Stasis', as we use the term, occurs after enlargement, not before; and complexification is after enlargement and then the brain reorganizes to fit the soul's uses. Habilis brain was used quite actively, as was the erectus larger brain, and then sapiens appeared, with not much different in lifestyle until 70,000 years ago. So 'big' ideas driving expansion has no sense of proof in the facts we have. Our enormous ideas caused shrinkage from complexification.