Increasingly brainless

Science is frequently employed as the poster child for civilization. The findings of empirical science are typically converted into corporate propaganda long before they enter general circulation. And some findings, specifically those that are radically inconsistent with the idea of civilization as a mode of human progress, are ignored into obscurity. 

Consider the data showing that the human brain has been shrinking over the last dozen millennia. Specifically, the volume of the average male brain is 1350cc today as compared to 1500cc 20k years ago (a whopping reduction of 10%). To the extent that brain size is a marker of intelligence, this would seem to suggest that civilization emerged only after humans were dumbed down relative to their pre-Neolithic counterparts.

One explanation links reduced brain size to increased population density and the need to curb aggressive behavior. With people living in closer quarters, aggressive behavior became increasingly maladaptive, so the theory goes. Since aggression tends to increase with age, one way for nature to decrease aggressive behavior is to slow down maturation (a process called neoteny). The gradual juvenilization of the adult population was brought about by selective pressures that led to the retention of child-sized brains into adulthood. So, not only did we become dumber as a species, we became more childlike as well.

Unfortunately, the capacity for lethal aggression is not the only characteristic that increases with maturity.

Where is the idea of civilized progress in all of this? Easy, according to the scientist/propagandists: our brains are smaller now, but they are also far more efficient!

Nice try. 

While there is ample evidence to support the immaturity hypothesis, there is absolutely no evidence that a decrease in brain size was accompanied by a concomitant increase in processing efficiency. It is likely that a Paleolithic human transported to our time would consider our wisest elders to be emotionally immature children, and look upon our "advanced" civilization as some kind of bizarre magical nursery for mentally retarded infants.