The primary function that is lost from an underdeveloped prefrontal cortex is impulse control.We all feel impulses to do bad things, but when you have a more developed brain and higher IQ, you weigh the long-term consequences of taking that specific action, and if they are negative to you/others, you avoid the action.White Europeans evolved in the north where weather conditions were brutally-cold, which forced the growth of their prefrontal cortex, as long-term thinking was necessary for surviva