Brain expansion (Evolution)

by dhw, Tuesday, August 11, 2020, 12:31 (1563 days ago) @ David Turell

dhw: Since brain change is known to be the RESULT of performing new tasks, it is not unreasonable to argue that in former times brains may have expanded as a RESULT of performing new tasks.

DAVID: The sapiens brain started in an expanded form from its beginning per the Moroccan new finding, and without any advances in artifacts or other new styles of living.

The Moroccan finding is the oldest yet. We don’t know the cause of expansion. That does not mean the only possible explanation is that your God stepped in one night and operated on their brains, skulls and pelvises.

dhw: I suppose I'd better repeat that NOBODY knows what tasks these were, and the invention of new artefacts was simply a concrete example to show how the process might have worked. The fact that there were no new artefacts found with the fossils of big-brained Moroccans is irrelevant. They may have performed other new tasks, or they may have interbred with other big-brained homos who had performed other tasks. New fossils are being discovered all the time, and the fact that the CAUSES of brain expansion remain a mystery does not provide one jot of evidence for your own solution to the mystery, which is that your God stepped in to operate on the Moroccans’ brains, skulls and pelvises – presumably knocking them out with some sort of divine anaesthetic while he did so.

DAVID: Your usual response to try to negate or hide your original theory that the implementation of new artifacts caused the expansion.

That was NOT my original theory! Why do you keep going on about it? Only a week ago, I quoted from my post of February 19, at the beginning of this discussion, a passage which even then I bolded: “pre-sapiens brain expanded when the capacity was too small to meet new requirements (e.g. the implementation and usage of new means of survival).” We both used the spear as a concrete example. The abbreviation e.g. (exempli gratia) means “for example”.

DAVID: It is all clearly in the record in the past. All we know is they lived in caves, tamed fire, wore skins, napped stone points, probably had some early word-like sounds and cross-bred with other homo forms. Living style not very advanced from the latest erectus groups, but lots more neurons to learn to use. Opposite to your theory which is new brain neuron webs used from the beginning of the new brain.

That is a misleading way of putting it. My theory is that the brain expands because it has to meet new requirements. Once these requirements have been met, there has always been a period of stasis during which the additional "brain neuron webs" do not produce anything NEW that requires further change. Stasis = no new development,which is what you say applies to the Moroccans. I don’t know if any of the characteristics you’ve listed were new enough to demand the additional “brain neuron webs” that led to Moroccan expansion. Nobody actually knows when humans first started to use fire or to wear skins, but in any case NOBODY KNOWS WHAT CAUSED BRAINS TO EXPAND. There’s a lot we don’t know. That’s why we come up with theories.