Fred Pearce
August 2014

Are there too many of us?

CC image courtesy of rp72 on Flickr

environmental SCIENTIST | The Contentious Issue | April 2014

We hear a lot about how the world’s population is soaring. The human total has now exceeded seven billion people, more than four times the figure of a 100 years ago. Many people, especially environmental scientists, fear that overpopulation is driving the destruction of the world’s resources and will one day make the planet uninhabitable.

But there is another story. A good news story about how the doomsters may have got it wrong. How the world is solving what has seemed about the most difficult problem for t he f uture of humanity. What’s more, it is being solved by the world’s poorest people, especially women. The people often seen as villains in the population story are turning into heroes.

The population bomb
The world was alerted most forcibly to the population problem in the 1960s by the US biologist Paul Ehrlich, in his million-selling book The Population Bomb. There was reason to be scared. Back then, women were having five or six children, and most of those children were growing up and having their own children.

As a result, the human population was doubling every generation. Doubling food production seemed impossible. “The battle to feed humanity is over,” Ehrlich wrote. “Sometime between 1970 and 1985, the world will undergo vast famines. Hundreds of millions of people are going to starve to death.”

Since then, the world’s population has gone from 3.5 to over seven billion. We have had some famines, but nothing on the scale that Ehrlich predicted. One reason is that global food production doubled ahead of time thanks to the ‘green revolution’ of high-yield crop varieties.

The bomb defused
That bought time. Time that has been used. Because the other thing that did not feature in Ehrlich’s doomsday prediction is that the population bomb is being defused. Today’s women have just half as many children as their mothers back in Ehrlich’s day.

The global average is now just under 2.5 each, which is very close to the replacement level. Allowing for girls who do not make it to adulthood, women globally need to have around 2.3 children to keep up numbers in the long run.

There is a reproductive revolution going on round the world. Half the world now lives in countries with fertilityrates that are at or below the national replacement level. That includes Europe, North America and the Caribbean, most of the Far East from Japan to Vietnam and Thailand, and much of the Middle East, where Iran has seen one of the most dramatic changes. In the past 25 years, the number of children born to Iranian women has crashed from eight to fewer than two. Women in Teheran today have fewer children than women in London or New York.

The mullahs and some politicians did not like it. In 2006, the then-president Mahmoud Ahmadinejad called for women to return to their “main mission” of having babies. But women were not listening, and even his own government ran a condom factory.

Some of this worldwide reproductive revolution has been happening because of coercive governments running the kinds of birth-control programmes that people like Ehrlich often called for back in the 60s and 70s. Most of this has been in China, where the government decides how many children couples can have. They call it the one-child policy, though there are a growing number of exceptions.

But the odd thing is that such government diktats may not make much difference any more. Ethnic Chinese women elsewhere in Asia have adopted what amounts to a one-child policy of their own. When Britain handed Hong Kong back to China i n 1997, it had the lowest fertility in the world — below one child per woman.

A falling trend
Family planning experts often say that women only start having fewer children when they are educated or escape poverty. Pessimists have feared that if the rising population stops people getting rich, they will get caught in a vicious cycle of poverty and large families. But in most places, even the poorest and least educated are deciding they want fewer children.

Take Bangladesh, one of the world’s poorest nations. Its girls are among the least educated in the world, and mostly marry in their mid-teens. You might expect big families. Yet they have on average fewer than three children. India is even lower at 2.8, half the figure in 1980. In Brazil, a hotbed of Catholicism, most women have two children. Nothing the priests say can stop millions of women getting sterilised.

I think something very simple is going on. Women are having smaller families because, for the first time in history, they can. In the 20th century, the world largely eradicated the diseases that used to mean most children died before growing up. Mothers no longer need to have five or six children to ensure the next generation. The population bomb went off in the years before reproductive habits caught up with medical advances. But it now looks like a very temporary phenomenon.

This reproductive revolution has also changed women and their place in society everywhere. Women are able to have two or three children and get on with a life outside the home. It is probably no coincidence that the reproductive and feminist revolutions have both spread round the world at the same time. Those revolutions are both very incomplete, but they are real and global.

There are holdouts, of course. In parts of the Middle East, traditional patriarchs still hold sway. In Yemen, where in remote villages girls as young as 11 are forced into marriage, they still have six babies. In parts of rural Africa, women still have five or more. But even here they are being rational. On a poor African peasant farm, children are useful from a very young age to mind the animals and work in the fields.

However, more than half the world now lives in cities, where children are usually an economic burden. There are no jobs in the fields. You have to get them educated before they can get a job. And by then they are ready to leave home. Urbanisation is everywhere helping to reduce fertility. We are used to seeing poor-world megacities as symbols of overpopulation. Maybe, but they are also part of the solution.

And the big story is that rich or poor, socialist or capitalist, urban or rural, Muslim or Catholic, secular or devout, with tough government birth control policies or none, most countries tell the same story. Small families are the new norm. That does not mean women do not still need help to achieve their ambitions of small families. But this is now about rights for women, not population control.

Population growth has not ceased yet. We may end up with another two billion or so before the population bomb is fully defused. This continued increase is mainly because the huge numbers of young women born during the baby boom years of the 20th century remain fertile.

But the world recently reached a new demographic milestone: peak child. The number of children in the world has stopped increasing. So, even though people are living longer, we can look forward with some optimism to the day when the world’s population as a whole peaks. After that, the world’s population may even begin shrinking.

The consumption bomb
What does that mean for the environment? Well, it is good news, of course. But, just as the population bomb was never really the problem, stable population is only part of the solution. Rising per-capita consumption today is a far bigger threat to the environment than a rising head-count. And most of that consumption is still happening in rich countries that have long since given up growing their populations.

Take today’s contributors to climate change. The world’s richest half billion people – that’s about seven per cent of the global population – are responsible for half the world’s carbon dioxide emissions. Meanwhile the poor 50 per cent are responsible for just seven per cent of emissions.

Or look at it another way. Economists predict the world’s economy will grow by 400 per cent by 2050. If so, only a 10th of that growth will be due to rising human numbers. It is the world’s consumption patterns – and how we produce what we consume – that we need to fix. We have not even begun to defuse the consumption bomb.

What is our demographic future?
Demographers used to believe that as countries develop and their birth rates fall, they will settle down at roughly replacement level. But the evidence of the great majority of countries that have got down to the replacement level is that they do not stop there. They carry on down, often to ultra-low fertility – below 1.5.

Often the lowest fertility rates happen in countries where the feminist revolution has made least progress. If forced to make a choice between working and children, young women will now mostly choose working. The results could be literally nation-destroying. If Italy gets stuck with present fertility levels, and fails to top up with foreign migrants, it will lose 86 per cent of its population by the end of the century.

By contrast, where men take a greater role in bringing up children, where the state intervenes to help working mothers, or where the labour market is sufficiently flexible, then fertility rates stay quite close to replacement. You can see that in Scandinavia, France and Britain, for instance. 

The other major demographic trend is ageing. As we live longer, and as fertility rates fall, ageing is becoming a global phenomenon. This is terra incognita. Our species has never lived in societies where there were more people above the age of 40 than below. But soon we will. Japan is already there. Before long, China will have a declining population and more old people than anywhere else.

Some say this is the new population bomb, and that we will never be able to afford to look after all those old people. It is hard to predict how an older world will turn out. But we will certainly have to think of the old not as a burden, but as human capital, a source of wisdom and experience. And we may change in more subtle ways.

At the height of the worldwide population explosion, the 20th century was almost literally taken over by teenagers. They were rampant consumers. But those days are passing. As the population bomb is finally defused, the world will settle down a bit. It might be more survivable, and plain nicer.

The youth century had two massive world wars and nearly destroyed itself with nuclear weapons. But it is an almost-universal rule that only countries with young populations have wars. So the chances are that we will not do that again.

Pessimists could be right that in the 21st century, ageing societies might lose the ability to innovate and solve the huge problems still facing us. But my guess – my hope – is that the 21st century will be more mature, less frenetic, less consumerist, and a more frugal and greener society. Older, wiser, greener. That is my optimistic hope for the future.

Fred Pearce is a london-based freelance author and journalist. He is the environmental consultant of New Scientist magazine. His books include Peoplequake (Eden Project Books).