Evolution and humans: big brain size uses energy (Evolution)

by David Turell , Wednesday, October 25, 2017, 15:27 (2584 days ago) @ dhw

DAVID: I know brains expanded in jumps with each new species in the advance of hominins to humans, and your approach does not fit the facts of brains becoming smaller among humans with increased use.

dhw: From the prioritization of brain mass you somehow extrapolated the claim that “the entire transition from trees to ground was a well-planned transition”. You then agreed that the brain did not change before pre-humans left the trees, which supports my argument that brain expansion was a RESPONSE to the new conditions and was not planned beforehand. As for brain shrinkage in Homo sapiens, we dealt with that in detail, my suggestion being that once the brain had reached a certain size, expansion was no longer an option and so complexification (rewiring) took its place, as exemplified by the illiterate Indian women, and this proved so successful that the brain no longer required its original mass. Do we really need to go over all that again?

I'll again ask, shouldn't you note that my scenario fits the facts as much as you think yours does? Also most of our giant pre-frontal cortex arrived long before we figured out how to be civilized and develop all the non-material concepts now present in the arts and sciences. It is still obviously size first use second.