These demographic trends are, unfortunately, only temporary. From the point of view of evolution, birth control is a disaster. I have done exactly the activity evolution has programmed me to do to continue the species, regularly, for over 20 years. Only twice did it result in children, and both times were conscious choices on my part. However evolution knows how to face these disasters. There is a small minority of p…
You said it, brother (sister?). In each country there are subcultures (religious fundamentalists, usually) that have birth rates well above replacement. Secular culture has managed to peel away many of their kids in recent decades but, with the kind of uninspiring, plasticky productions currently streaming out of Hollywood / big label music, that process is about to change. Let's just say, your radio is likely to pla…
And while Mormon's rapid breeding might prevent demographic malaise, the rapid breeding of low conscientiousness people won't - the very trait that causes them to breed rapidly also causes them to be generally unproductive.