Without immigration, most developed countries would face massive depopulation. In fact, half the population of the Earth lives in countries with sub-replacement fertility.
The threshold for a sustained population is a fertility rate of 2.1. Taiwan South Korean and Singapore are at 1.2, Japan and Germany are at 1.5, the whole European Union and Canada are at 1.6, Australia, the United Kingdom and the USA are at 1.8.
Yet Earth’s population is still growing. Where is the population growth? Niger, Sudan, Somalia, Mozambique, Uganda, Congo, Afghanistan… Or, to put it another way, in the poor countries.
If the current trends are maintained, by 2050, Japan will count about 100 million inhabitants or over 25 million fewer than the current count. By then, there will be many more Japanese in their seventies than in any other 10-year age group.
In Europe, Germany is currently the largest countries with 80 million inhabitants. If the current trend continues, by 2050, it should count no more than 75 million people. Germany is going to need millions of people over the next two decades just to sustain its population.
What about China? They stand at 1.4 billion people. By 2050, they should have fallen to 1.3 billion people… It is no wonder that China recently dropped its one-child policy.
Of course, countries like the USA, Canada and France are still growing… but that’s largely because of immigration, often from countries where people reproduce more readily.
Won’t better health and longevity lead to renewed population growth in the rich countries? No. Excluding immigration, population growth is almost entirely determined by fertility. That is, what matters is how soon and how many children women have. Even if Japan’s bet on regenerative medicine delivers exceptional benefits, it won’t make much of a dent on the population curve. If you could, somehow, multiply your lifespan without having any more children, you’d only add “1” to the population count. And improved health and medicine decrease your effective fertility. Healthier women who receive great medical care for themselves and their children tend to have children later, if at all, and tend to have fewer of them.
You’d think that being few in a rich country is not a major problem. But depopulation means closing down rural towns. It means fewer scientists, fewer nurses… And because we have not yet a handle on age-related diseases, it means more retirees needing help with fewer working individual per capita. Worried about imminent depopulation, Italy recently launched an ad campaign reminding ladies to hurry up and have babies. In Denmark, they teach pupils about the need to have more children.
It is true that a child is a mouth to feed. But a child might grow up to build new technology, to care for the sick, and so forth.
At least as far as the richest third of humanity is concerned, there are not too many people, and there might be too few.