Perhaps also interesting in this context is the fact that the human brain has been shrinking over the last 20,000 years: http://discovermagazine.com/2010/sep/25

Perhaps also interesting in this context is the fact that the human brain has been shrinking over the last 20,000 years: http://discovermagazine.com/2010/sep/25-modern-humans-smart-why-brain-shrinking http://discovermagazine.com/2010/sep/25-modern-humans-smart-...