That item reminded me of perhaps the most remarkable article I read all last year, a New York Times piece entitled "What Happens When Global Population Peaks." It argues that the population of the world will start to drop sometime between 2060 and 2080 after hitting a peak approaching ten billion. If present trends continued, the population would continue to decline -- precipitously.
It would take about 300 years, say to 2400, to fall to two billion (where it was circa 1927), but without significant changes in human behaviour, the reduction could be steady and steep. A preference for small families is conquering the world -- both articles give reasons why. Unless that trend gives way to some new baby boom, the decline would continue indefinitely and take global population rapidly toward to a population of only a few hundred million people or less in the world -- the number it had 3000 years ago.
Demographers have a good reason for mostly declining to calculate populations beyond about 2100: because there can be no certainty what a population yet unborn will do. Also, historians know that present trends never continue forever. Things will change, though not necessarily to restart population growth.
Still, it 's a startling thought to contemplate a world looking relatively empty of humans not so very far in the future. On a scale of eons, probably a good thing.
