Brain expansion (Evolution)

by David Turell , Saturday, July 11, 2020, 20:00 (1384 days ago) @ dhw

DAVID: You have abandoned your original thought that an idea in a previous brain forced the new expansion as it was implemented by the new brain. Progress!!

dhw: How the heck to do you arrive at that conclusion? I am saying that I do not know what new “idea” triggered the expansion! We took the spear as an example, because artefacts are the only concrete evidence we have. The trigger could have been changes in the environment or new discoveries or experiences that forced the existing brain to implement new ideas concerning modes of living. Whatever may have been the new “idea”, it would have arisen originally in the old smaller brain, and its implementation would have exceeded the capacity of that brain’s complexification and so would have necessitated additional cells.

Still defending your natural view of expansion. Fine. We clearly disagree. I'll stay with God who decides when in evolution a larger brain will appear. All we know about human brains is they shrink when heavily used, after having enlarged at first in areas that provide the soul with more complex conceptual thinking areas. That is basically where all enlargement takes place from Lucy-likes and onward.

dhw: You have agreed explicitly that the brain shrank because the efficiency of complexification (an autonomous process) made certain cells redundant. Expansion entails the addition of neurons! The fact that this takes place within the confines of the existing sapiens skull does not alter the fact that the brain can expand itself. Both processes result from the “mechanism” you say your God implanted in the brain (bolded above) – a mechanism which acts autonomously and which I call cellular intelligence.

DAVID: The addition of some hippocampal neurons has not expanded the brain, similar to past expansions. They are really part of the plasticity and complexification, all of which has only reduced brain size.

dhw: Of course it hasn’t expanded the brain, but it has expanded part of the brain. Addition = expansion. And if there is an autonomous mechanism for small-scale expansion in the modern brain, it is not unreasonable to suppose that the same mechanism caused expansion in the earlier brain, but on a much larger scale.

Skulls and brains shrink is the only example we have in sapiens even if neurons are added in the hippocampus. It is all part of plasticity and complexification. I suspect, as stated before, both processes were present to small degrees in earlier hominin/homo brains, neither of which would enlarge brains.

DAVID: How God offers the instructions is always debatable. How do you think God does it? […]

dhw: […] Your strict guidelines entail a 3.8-billion-year-old computer programme or direct dabbling for every single life form, natural wonder etc. as above. You have not come up with any alternative, but of course you are free to believe whatever you wish to believe.

DAVID: Thank you, and in the other thread I show you that Behe and I both believe in DNA pre-programming. Dabbling would be the gene destruction Behe describes.

dhw: Have I got this right? You (and Behe?) appear to believe that every single life form, econiche, lifestyle, strategy, natural wonder etc. in the history of life was preprogrammed in the first cells, and in order for each one to emerge separately, your God took out the umpteen million programmes for all the other life forms, econiches, lifestyles, strategies and natural wonders, leaving just the one. If this is wrong, do please explain what you (and Behe?) think your God preprogrammed and what he dabbled.

That is the point of Behe's new book! Why couldn't God program it all in the beginning? He may have programmed the evolution of the Big Bang to the universe we see today, the Milky Way and the Earth all at their beginnings. Then sat back and watched. If something evolved in a way He had not planned, He could then step in and correct it.