Evolution: more genomic evidence of pre-planning (Evolution)

by dhw, Saturday, March 27, 2021, 11:35 (1335 days ago) @ David Turell

DAVID: You never explain stasis, which I see as a consequence of a brain appearing which is too large for current needs, and is the actual history of what happened. God speciates in anticipation of future use.
The above was your reply to my theoretical explanation of stasis, which I shall now repeat for the umpteenth time. But first, why on earth would an overlarge brain result in stasis? And no, a brain too large for current needs is NOT the actual history of what happened. That is your theory. The sapiens’ brain expanded from 1200cc erectus to 1350cc, just as all earlier brains expanded by similar amounts. There are various possible causes, such as new tools or weapons, clothes, new environments to cope with, new discoveries, use of fire etc. Once each brain (including sapiens) had expanded by meeting the new requirement, it did not need to expand any more (complexification could cope) until there was another new requirement which exceeded its existing capacity. (Explanation of stasis.) It was never too large. The sapiens brain was never too large either. It was adequate for all sapiens’ needs for 300,000 years. But then – again we don’t know why – new requirements arose, but as further expansion would have required major anatomical changes, enhanced complexification took over. And it proved so efficient that some of the existing cells were no longer required – hence shrinkage. You have never offered one single reason for rejecting this hypothesis, but merely go on repeating your own beliefs as if they were “the actual history of what happened”. I do not ask you to believe my theory. I only ask you to provide one logical reason for rejecting it.

DAVID: The shrinkage doesn't help your theory.

dhw: My theory doesn’t need help from shrinkage. It only requires an explanation which I have given you and which you have ignored.

DAVID: I don't ignore it, as your description of stasis doesn't explain that it must occur.

I have never said it MUST occur. I have explained why it DID occur, and you have not provided one single reason for rejecting my explanation.

dhw: You keep trying to limit attention to sapiens.

DAVID: It is the only brain we can study. [...] .

dhw: And since the only brain we can study shows that the brain changes IN RESPONSE to new requirements (though one section has expanded), I would suggest that the only brain we can study offers more support to my theory than to yours. And it is NOT the 200 cc that makes the difference, but the enhanced ability to complexify. 300,000 years later, some of the cells could even be jettisoned! You say in the next exchange, there was no initial change in lifestyle!

DAVID: Which means stasis after huge enlargement.

How huge is huge? Our enlargement was no “huger” than preceding enlargements, stasis occurred after every enlargement (as explained above), and how does this comment invalidate the point that the only brain we can study shows that the brain changes IN RESPONSE to new requirements and not in anticipation of them?

SURVIVAL
dhw: You launched your usual attack on Darwin,....

DAVID:: My attack is on the bastardization of his solid theory which is only common descent.

dhw: No it isn’t. You attacked his theory that the purpose of evolutionary adaptations/innovations was to improve chances of survival, but you consider that to be a “weak approach”. […]

DAVID: […] Our current abilities are far beyond the needs for living a life totally in natural wilderness as erectus and early sapiens did, housing themselves in caves and wearing skins. The brain from 315,000 years ago allowed that.

dhw: Exactly. The final expansion proved adequate for all the requirements for survival….

Your switch to sapiens enabled you to change the subject from your refusal to accept Darwin’s theory that the purpose of evolutionary adaptations/innovations was to improve chances of survival. May I take it that you now accept his theory?

dhw: …And when, 300,000 years after that final expansion, there were new requirements – whether connected with improved chances of survival or with other matters – the brain could not expand any further without creating problems for the anatomy (my proposal), and so enhanced complexification took over as the means of meeting them, as we know from research into “the only brain we can study”. You keep supporting my theory in your efforts to oppose it!

DAVID: Just the opposite. Humans had to learn to use the overexpansion and the stasis period demonstrates the time it took.

I propose that there was no overexpansion, and I have no idea how you can learn to use something without producing anything. Stasis means nothing new, and it applied to all stages of expansion, as explained above. I now eagerly await one logical reason for your rejection of my theory – other than the fact that it is the opposite of your theory.