For decades, if not centuries, demographers have worried about what they called the overpopulation of the Earth. Sooner or later, they thought, the population would grow toward the limits of our planet. But in 2019, Darrell Bricker and John Ibbitson published their book Empty Planet, arguing that these worries are essentially over. Instead, surprisingly, they predicted the opposite: the world might actually run out of people.

Around the middle of the current century, they expect that the world population will begin declining. And this decline, the authors predict, will never end. And that will have dire consequences for our current way of living and doing business:

In short: economic growth is hard to sustain if the population declines. Charles Goodhart and Manoj Pradhan spell out the economic consequences of demographic change in The Great Demographic Reversal: Ageing Societies, Waning Inequality, and an Inflation Revival.

Now, newer studies predict the tipping point will arrive as early as 2030. The reversal of centuries of population growth itself is, of course, not an issue. Activists of all kinds have long called for measures like birth control to avoid overpopulation. The issue is that we, as a global humankind, don’t have a plan for how to deal with the consequences of a shrinking world population.

It’s pretty clear that a shrinking population isn’t sustainable. Why? Because many of our systems will collapse if – or when – they run out of people.

The crux in the long term

So far, a country like Germany has kept its population stable and even growing, despite a surplus of deaths, through immigration. Starting with the now-infamous guest workers of the 1960s and 1970s, immigrants have filled the gaps left by the births deficit of the incumbent population. But immigration couldn’t stop the ageing of the population.

For decades, Germany has outsourced around a third of the births required to maintain its population to other countries. This can only continue as long as the country remains attractive to immigrants – and the supply of potential immigrants is large enough. I’ve deliberately put this into hard, economic terms. As the world population moves from growth to decline, competition to attract immigrants will heat up.

This is a question of qualification. For a while, Germany had attracted migrants from Poland, Romania and other Eastern European countries. They were people who did not come to Germany to escape, but instead because they had labour market opportunities here. However, this influx is gradually levelling off. This is because these countries increasingly need their labour force themselves. The largest number of returnees from Germany is already heading back to Romania.

The demographic crux is a long term issue. Even if Germany could bring back the birth rate to a sustainable level, which is highly unlikely, it wouldn’t be enough on its own. The people who weren’t born because of the sudden drop in birth rates can’t have children – because they don’t exist. We are inevitably moving towards an older society that is increasingly characterised, and supported, by migration.

Accelerating collapse

The last remaining continent with fertility rates above replacement level and thus a growing population will be Africa. For a while, most of the world will perhaps compete for African immigrants. But we could also see other scenarios, with regions or entire countries collapsing under the weight of their over-aged population, sparking new waves of migration.

People will start moving away from over-aging and declining regions to more prosperous ones, thus accelerating their descent.

Putin’s Russia is a potential candidate for collapse, with dire demographics and an expensive war that drives fertile men out of the country or into death on Ukrainian battlefields. As a global top-ten country by the number of inhabitants, with a huge landmass and a multitude of ethnic groups, Russia could potentially collapse into a bunch of independent or semi-independent countries.

But wait, shouldn’t the population decline make wars less likely? It depends. We could see “depopulation wars” waged against or by declining countries. Whatever happens, demographics is a factor that warrants strategic attention.

That said, it’s not all doom and gloom here. As the European Union has put it in a demography report:

The on-going demographic transition also creates opportunities for both individuals and society as a whole. As people live longer and healthier lives, they enjoy more possibilities for personal and professional development. As businesses and employment practices adapt to a shrinking workforce, underrepresented groups may get more opportunities to put their talent to use in the labour market.

The flip side of an ageing population is that many people live longer and healthier lives – an achievement in itself. There is the promise of a silver economy, tailored to the needs of older people, that provides innovative and, not least, digital services. A 2018 study – more demographics – projected the European silver economy to reach €6.4 trillion and 88 million jobs by 2025 – equivalent to 32% of EU GDP and 38% of the Union’s employment.

Demographics prompt people to work longer

The Baby Boomer generation is already working longer and retiring later than their predecessors:

People keep working because they want to and because they have to, and sometimes a mix of both.

This trend isn’t limited to the US; the same is true for Germany. It’s an opportunity and a necessity at the same time. Despite recent advancements in AI, not every task or job can or will be automated – but automation can and will change jobs, thus keeping older people in the job market.

How long will the decline of the global population continue? This is hard to predict, even by demographic standards. If fertility rates below replacement levels persist for more than a generation, as already is the case for many Western countries, the trend becomes almost irreversible. However, new societies with higher fertility might emerge. They could enjoy an evolutionary advantage in an otherwise shrinking world.

The outcome of all this depends on how well our global civilisation adapts to the groundbreaking population decline. Evolution is a game of adaptation.

Picture by Ryoji Iwata | Unsplash.