Evolution and humans: more on learning to read (Evolution)

by dhw, Thursday, November 08, 2018, 11:35 (1780 days ago) @ David Turell

TONY: Except that the sympathetic nervous system engages in preparation for an event, and the alterations can become part of the programming and be considered via epigenetics.

dhw: Sorry, but I’m not sure what you’re referring to. How does the “sympathetic nervous system” prepare for something it knows nothing about? Once the brain/body has changed, certainly it will be programmed to perform the new tasks, and I have no doubt that epigenetics plays a major role in evolution.

DAVID: Stepping in for a bit of medical education. The sympathetic nervous system is part of the autonomic nervous system:
"The sympathetic and parasympathetic systems are both components of the autonomic nervous system of the brain. They act in collaboration with each other to sustain the body’s homeostatic state."
Obviously the sympathetic system knows what is happening.

Thank you, but the context of this was my contention that the brain changes in response to new concepts and not in anticipation. I still don’t understand how the “sympathetic nervous system” can prepare for something it knows nothing about.

DAVID: The brain areas that assumed new duties already existed and were given the ability to change as necessary when they were created. Why do you interpret that fact differently?

dhw: I am referring to your insistence that your God changed the pre-sapiens brain before it could conceive the spear, changed legs into fins before the pre-whale entered the water, changed the anatomy before pre-humans descended from the trees – i.e. that every evolutionary innovation was planned in advance of changes in conditions. The brain like all other cells/cell communities RESPONDS to new conditions; there is no evidence that cells/cell communities change in anticipation of new conditions.

DAVID: You stay blind to the fact that a big brain appeared before all the new concepts were developed.

As you well know, pre-sapiens brains gradually increased in size, and I’m sorry, but the H. sapiens brain (if that’s what you mean by a “big brain”) did not appear before such new concepts as tools, weapons, use of fire etc. As regards the new concepts which appeared after the arrival of the “big brain”, why have you ignored the answer I already gave you? “In order to avoid repeating our past discussions on the subject, I’d better add that once the brain/skull had reached its optimum size, new uses were implemented through complexification, not expansion, and the efficiency of this has even resulted in a degree of shrinkage.”

DAVID: See my entry today on how fungus changed the Earth, and was prepared to do so in advance!
Note my bold: the algal ancestors of land plants, a group called ‘charophytes’, were equipped to communicate with fungi well before they encountered them.

Thank you for this intriguing article (and for all the others you posted yesterday). As usual, you prefer to ignore the fact that living organisms are composed of cells, and the whole point of my hypothesis is that cells from the very beginning were “equipped” with their own form of intelligence. You cannot have any kind of cooperation, including symbiosis, without some means of communicating. So of course the algae and fungi were equipped to communicate. Every form of multicellular life depends on the ability of its cells to communicate, and that ability must have existed before the cells cooperated.

DAVID (under “Introducing the brain”): Rodent research makes the point that mental ability is increased by vigorous exercise:

dhw: The point could hardly be clearer. It is “exercise” that changes the brain, even to the extent of enlarging some parts and developing new neurons. If we go back into the past, the same process must have taken place in pre-humans – namely, that “exercise” in the form of implementing new concepts would have changed the brain, and the resultant increase in volume would have required a larger skull to house the larger brain. Can you fault the logic?

DAVID: Perfectly logical, with one huge exception: we have no idea why the brain grew so large from its smaller size before it was used as in today's humans. The mice did not have exploding skulls in this study, only plastic alteration of the brain that already existed. And we know that plasticity shrinks existing brains

That is precisely what I am trying to explain: “exercise”, as in the implementation of new concepts, changes the brain. In pre-humans, I propose that the capacity of the brain was not large enough to cope with whatever those concepts were, and so it had to expand (just as it does now in certain areas of the brain when they become the main area of activity). The rest of the explanation – including shrinkage – is contained in the paragraph which you ignored.

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