Civilization Is Making Humanity Less Intelligent
Intelligence and the capacity for abstract thought evolved in our prehistoric ancestors living in Africa between 50,000 and 500,000 years ago, who relied on their wits to build shelters and hunt prey. But in more civilized times where we no longer need to fight to survive, the selection process which favored the smartest of our ancestors and weeded out the dullards is no longer in force.
Harmful mutations in our genes which reduce our “higher thinking” ability are therefore passed on through generations and allowed to accumulate, leading to a gradual dwindling of our intelligence as a species. Gerald Crabtree, a developmental biologist at Stanford University, explained in the Trends in Genetics journal that a mutation in any one of 2,000 to 5,000 particular genes could lower our intellectual and emotional ability. Our development of intelligence genes “probably occurred in a world where every individual was exposed to nature’s raw selective mechanisms on a daily basis,” he said, but the same pressures do not apply today.