13/11/2012 07:02 GMT | Updated 13/11/2012 12:15 GMT

Modern Life Is Making Humans Dumber, Says Stanford University Study

Modern society clearly has its benefits – hot showers, supermarkets, transport infrastructures and so forth.

But research suggests that all this convenience and organisation is actually harming our intellectual and emotional abilities.

According to a Stanford University study, the genes that give us brain power are particularly susceptible to mutations that lower intelligence.

The problem is that the structure of modern society means that humans generally still survive, even with these mutations present.

For instance, thousands of years ago, if humans couldn’t figure out a way of surviving in cold weather, they died and the smarter humans that could, survived.

In other words, there was selective pressure acting on the genes required for intellectual development.

These days we don't need to be clever to survive, because we have modern society with all its amenities and support to keep us going.

“The development of our intellectual abilities and the optimisation of thousands of intelligence genes probably occurred in relatively non-verbal, dispersed groups of peoples before our ancestors emerged from Africa,” said the study’s author, Dr Gerald Crabtree.

Dr Crabtree estimates that humans peaked intellectually at around 4000 BC and that within 3000 years (about 120 generations) we have all sustained two or more mutations harmful to our intellectual or emotional stability.

However, there’s no need to worry, because we’ve been smart enough to advance our scientific understanding of genes to the extent that we’re bound to figure out how to eradicate the mutations.

“I think we will know each of the millions of human mutations that can compromise our intellectual function and how each of these mutations interact with each other and other processes as well as environmental influences,” said Dr Crabtree. “At that time, we may be able to magically correct any mutation that has occurred in all cells of any organism at any developmental stage. Thus, the brutish process of natural selection will be unnecessary.”

The hypothesis was published in the Cell Press journal Trends in Genetics.

Key Signs Of Human Evolution

The appendix

Yes, it really doesn’t have any function at all, but some researchers believe it once helped to process cellulose from a bygone leaf-rich diet


It used to form part of a tail, but since we no longer swing around in trees it has a role supporting muscles when we sit down.

Wisdom teeth

Completely useless now, wisdom teeth used to help us eat plants as quickly as possible, when grabbing all the nutrients we could was all-important in a supermarket-less society.

Goose bumps

When we were a lot hairier, goose bumps would appear when we were cold, pushing the hair up and trapping air to help keep us warm. However, natural selection vanquished thick hair.

Plantaris muscle

At the back of your foot is a muscle we used to use for holding objects with our feet. Not so necessary now, so it’s evolving out of humans to the extent that 9% of us are born without it.