Brain expansion (Evolution)

by David Turell , Tuesday, August 11, 2020, 22:43 (1563 days ago) @ dhw

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

dhw: 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”.

I still interpret your bolded theory the same way: the brain expanded (naturally)to create something new that was thought of by a previous smaller brain: the Moroccans had no new lifestyle and no new artifact. There are no facts to support your conjecture.

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.

dhw: 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.

That is a better explanation of your natural theory of brain expansion. Latter forms of erectus had fire and skins. The Moroccans offer no support, so your theory stays pure theory.
I'll stick with God as engineer. The facts we have fit my theory better, IMHO