Chimp vs. human brain (Introduction)

by dhw, Saturday, December 08, 2012, 14:51 (4369 days ago) @ David Turell

DAVID: It is not that ours is four times larger in 6-8 million years. There have been major reorganizations and modifications, as shown in new studies of paleoneurology:
"Many neo-Darwinists seem to be under the completely false impression that the human brain is merely a scaled-up, more powerful version of the chimpanzee brain. Nothing could be further from the truth: the two brains are radically different. In addition to the massive growth in the human brain over the last three million years, there have also been massive reorganizational changes in the human brain, which are not easy to account for on a Darwinian paradigm. The major reorganizational changes, which are listed in the paper,"Evolution of the Brain in Humans ... Paleoneurology" by Ralph Holloway, Chet Sherwood, Patrick Hof and James Rilling (in The New Encyclopedia of Neuroscience, Springer, 2009, pp. 1326-1334), include the following: -(1) Reduction of primary visual striate cortex, area 17, and relative increase in posterior parietal cortex, between 2.0 and 3.5 million years ago; 
(2) Reorganization of the frontal lobe (Third inferior frontal convolution, Broca's area, widening prefrontal), between 1.8 and 2.0 million years ago; 
(3) Cerebral asymmetries in the left occipital, right-frontal petalias, arising between 1.8 and 2.0 million years ago; and 
(4) Refinements in cortical organization to a modern Homo pattern (1.5 million years ago to present)."-http://www.uncommondescent.com/intelligent-design/could-the-internet-ever-be-conscious-...-http://www.columbia.edu/~rlh2/2009.Holloway_Sherwood_Hof_Rilling.sm.pdf-We "R not chimps. Even if we look somewhat alike. I'm not even sure we should be classifed as primates, based on our form of consciousness.-These are all reorganizations (i.e. not innovations) of one sort or another. Your basic argument has always been that the human brain is different in kind, not degree, from that of other animals, and underlying that argument is your belief in evolutionary teleology ... namely that God planned evolution to culminate in us humans. However, if you believe as I do that all forms of life descended from earlier forms, you will agree that humans and chimps branched out from earlier forms going right back to the time when single-celled organisms combined into multicellular. One can argue that amoebas, spiders, eagles and elephants also differ in kind from one another and from us, and since they all still exist, presumably evolution was also planned to culminate in them too. I'm not disputing the uniqueness of our consciousness. I'm simply uncomfortable with the idea that every branch of evolution, both extant and extinct, was geared to us. Do you think God deliberately tinkered with the brain mechanisms of our distant ancestors, and also with the genetic makeup of spiders, eagles and elephants, or do you think they all developed naturally from the adaptive and innovative mechanisms that drive evolution?-********-The first of these websites raises a separate problem that I would like to deal with on a separate thread (Panpsychism), but the argument is directly connected to the above.