These are strange days and one takes one’s entertainment where one finds it. For me, it means taking a break from the world occasionally by reading some extremely funny subreddits on the social media platform Reddit. One of my favourites is called r/mildlyinteresting.

In a world where everything seems to scream at you, it’s nice to know there are other people out there who are interested in things that are only mildly interesting. The subgroup includes things like people who post pictures of a hotel that changes the lift mat three times a day, from the one in the morning that says Good Morning, to the one at midday that says Good Afternoon, and then Good Evening. And so on. Things that are only mildly interesting are curiously funny.

The New York Times published a story this week that there are now 10 million empty homes in Japan, which is of course a consequence of a declining population. I can’t decide whether this is mildly interesting or actually interesting. The argument in favour of this fact being mildly interesting is that over the years, we have seen many population growth catastrophists.

This trend started with Thomas Malthus, who at the turn of the 18th century calculated that world population was growing exponentially and food supply was growing in a linear fashion. Eventually, he argued, there would be mass starvation. The part Malthus got right, of course, was population increase, which has indeed grown at an exponential rate. The part that he got wrong is that resources have grown exponentially too. 

But this didn’t stop population catastrophism, which has returned sporadically, and for some reason was particularly popular in the 1970s, so much so that China pulled an extreme version into policy, adopting the one-child policy. But for various reasons, these theories have proved false. Productivity has increased disproportionately; scientific progress in the efficiency and production of food has been extraordinary. And then there is the thing academics and politicians don’t like to talk about: the gradual adoption of free markets around the world has massively improved global food production.

Still, population growth is just eye-popping. It took all of human history until around 1800 for the world population to reach 1 billion people. The fifth billion happened in only 13 years. And yet, for all that, although some areas of the world are very crowded, the global average population density is still around 30 people per square kilometre.

And now we have a new phenomenon, as The New York Times article suggests: countries with sharply declining populations. The overall global fertility rate is coming down at a very fast rate now. India has just overtaken China as the world’s most populous nation with about 1.4 billion people, but it’s possible that China’s population will be only about 700 million by 2100. Global population, now around 8 billion, could peak around the same time at a little over 10 billion, and start declining.

Despite the concerns about the effects of climate change and so on, population growth is probably less of a concern than the catastrophists would have us believe – or at least I think so. But there is an argument that this is not all “mildly interesting” but actually “very interesting”, which is particularly true if you look at population growth from a geo-political point of view. 

Population size and geopolitical heft do somewhat overlap. The reason is partly that economic prowess tends to follow – often with huge lags and sometimes not at all – population size. The whole standoff between the US and China at the moment is based partly on the competition for global economic dominance because, for the first time, the US and China are roughly the same size economically.

And you know where this is particularly relevant? Here, in Africa. There is no place on Earth growing as fast as Africa in terms of population. These increases seem to appear out of nowhere because they are gradual. But when you look at the numbers, it is amazing.

For example, test your general knowledge quickly: 1) Place these three countries in order of population size: SA, Tanzania and the DRC. 2) By what year will Tanzania’s population outnumber the UK’s? 3) When will SA’s population be greater than Italy’s? 4) Are Africa’s five biggest countries larger than Europe’s five biggest countries in total population size, and if so by how much?

Of course, you knew the answers: the DRC is the biggest, Tanzania second, and SA third. Tanzania overtakes the UK in about five years; SA overtakes the UK in around 2040, assuming the UK’s growth rate doesn’t fall further, which it most likely will. Question 3 is a trick question: SA is already larger than Italy, Europe’s fourth-largest country. And Africa’s five largest countries – Nigeria, Ethiopia, Egypt, the DRC and Tanzania – have populations around twice that of Europe’s top five, Germany, the UK, France, Italy and Spain.

Of course, size does not equate to economic prowess; the US is around the same size economically as China while it has a quarter of the population. Yet, answering these questions, it helps to explain why African countries are growing economically as fast as they are. And why their social problems are increasing at a frenetic rate. 

Still, before catastrophism takes over once more, it’s worth noting that extreme poverty is now falling fast in Africa. By one count, around 56% of Africans lived in extreme poverty, which was measured in 2017 at around $2.15 per day. That proportion is currently around 35%. That is an amazing decline, although with population increasing so fast, the absolute number of Africans living in extreme poverty is probably still increasing.

All in all, when you think about it, population growth numbers are much more than “mildly interesting”, but they don’t tell the full story. Sometime in the not-too-distant future, this is all going to be very significant from a geopolitical point of view. BM/DM