A Shrinking Planet
By Nayyer Ali MD
One of the major trends that has shaped the modern world is the dramatic rise in human populations. Britain in 1800 had only 10 million people, that climbed to over 40 million by 1900 despite vast numbers moving to North America and other locations. Pakistan had 37 million in 1950 and over 210 million now. China has over 1.3 billion people, more than the entire population of the globe when America declared independence. According to the UN, they project that today’s population of 7.5 billion will rise to 11 billion by the end of this century before finally coming to a halt.
But there is actually a good chance that we will never have 11 billion people. In large parts of the world, the total fertility rate (TFR), the number of babies born on average by each woman, is collapsing. To keep long-term population stable, the TFR should be about 2.1 babies. But in almost all advanced economies, it has dropped well below that. In much of Europe it is about 1.5, and in nations like Italy, Spain, Japan, and South Korea it is even lower than that. China adopted a one child policy (that had a lot of loopholes allowing some couples to have two children) back in 1980. That policy worked great to slow down China’s population growth, but it has in some ways worked too well. Last year, the Chinese finally abandoned the policy as the number of babies born in China collapsed down to a level not seen since 1960, when China had less than half as many people.
This decline in fertility is being seen even in poor countries. India is under 3, and Iran is under 2. Bangladesh is basically at replacement, while Pakistan is still relatively high at 3.5, but much lower than 30 years ago. While Bangladesh (East Pakistan at the time) also had 37 million people in 1950, its population growth has been much slower, and while demographers project Pakistan will peak at 300 million around 2050, Bangladesh is going to peak at only 200 million people.
The problem with this collapsing fertility is that it is going to lead to societies that are aging rapidly and actually shrinking in population. This will be a real problem because there will be a shortage of workers paying the taxes to support the pensions and healthcare needs of the growing number of retired elderly citizens. China’s labor force has already peaked in size and is going to start shrinking. It will shed an astounding 200 million workers by 2050, a fact that has huge geopolitical significance. Italy, Spain, Russia, and Japan are all set to see a major decline in their population over this century.
The United States will do better than most other advanced nations because it remains rather open to immigrants, who will replenish and expand the workforce. While TFR in the US has slipped below 2, the population is still expected to expand this century. By 2100, the US will likely be more than half the size of China in population, and given its more advanced economy, will still be the dominant power.
The wild card for total population in the century will be what happens in sub-Saharan Africa. In those nations TFR is still a very high 4.5, which is lower than pre-modern numbers but still high enough to add 3 billion Africans to the current 1 billion by 2100. There were only about 150 million Africans in 1900 below the Sahara, so to reach almost a billion now is remarkable. Where humanity ends up in 2100 will depend primarily on how TFR plays out in Africa.
We do know what brings down TFR rapidly. The formula is actually rather simple. Educate girls, and move people from villages to cities. Those two factors alone explain much of the decline in TFR in every country around the world. If education and urbanization proceed at current trends, then Africa will likely only reach 2 billion people, and the global total will peak around 9 billion. If these forces are strengthened, analysts think we could peak at 9 billion but then decline rapidly to 7 billion by the end of the century. It is conceivable that there will be fewer humans in 2100 than there were in 2000.
Many countries are grappling with below replacement fertility. In Hungary the government just announced that women bearing four or more children will be exempt from all taxes. In France, the government provides generous maternity and childcare benefits. But in many nations, the problem women perceive is that it is difficult to balance a career and marriage and family. This is a big issue in places like Italy and Japan where traditional roles have not changed much. Women are choosing not to get married and have children.
What happens after 2100? If humans everywhere have TFR less than 2 for generation after generation, we as a species will literally shrivel away. Once a generation fails to reproduce itself, its descendants would actually have to have a TFR well over 2 to just catch back up, otherwise the population will permanently shrink.
Is modern life, with its hustle and bustle, high costs, and infinite distractions, fundamentally incompatible with most men and women wanting to raise several children? Or will those living a hundred years from now be so rich and prosperous that having children becomes much less of a burden, and the biological urge to reproduce reasserts itself? The answer to that question may determine the long-term future of mankind. Science fiction films showing humanity expanding into the galaxy are predicated on a human race that is constantly growing, if the reality is a long-term shrinkage, why would we ever leave Earth?
