Lead and cadmium in food caused by cheap fuel and roads closer to farms is also negatively affecting population IQ.

Then there’s the internet.

"We've heard that a million monkeys at a million keyboards could produce the Complete Works of Shakespeare; now, thanks to the Internet, we know this is not true." [1]

[1]: https://www2.eecs.berkeley.edu/Faculty/Homepages/wilensky.ht...