Reuters / A recent study in the journal Trends in Genetics argues that humans lost the evolutionary pressure to be smart once we started living in dense agricultural settlements several thousand years ago.
“The development of our intellectual abilities and the optimization of thousands of intelligence genes probably occurred in relatively non-verbal, dispersed groups of peoples (living) before our ancestors emerged from Africa,” said study author Gerald Crabtree, a researcher at Stanford University, in a statement.
The study says early humans had to be constantly on their toes to find food and shelter, and to be on the alert for predators.
But after the spread of agriculture, providing regular access to stored food, genes responsible for intelligence were under less pressure from the daily challenge of staying alive.
“A hunter-gatherer who did not correctly conceive a solution to providing food or shelter probably died, along with his/her progeny, whereas a modern Wall Street executive who made a similar conceptual mistake would receive a substantial bonus and be a more attractive mate. Clearly, extreme selection is a thing of the past,” the researchers write in the journal article.