The Population Question

Reducing birthrates is a long term solution but won't avert imminent ecological disasters

A couple of readers have asked me why I didn’t discuss the ecological implications of population in my book, A Drop of Grace. Obviously, the more people there are on the planet the more natural resources we will consume. Quite shockingly, the current population is 14% of all humans who have ever lived. That explains a great deal about why we are consuming natural resources at ever accelerating rates. According to the standard model of economics, population is one of three key drivers which determine the rate at which we are manufacturing goods, and in our current social structure, consuming natural resources. So why did I not delve into the issue in my book?

One of the main reason was because reducing birth rates is not an effective way to get ourselves out of the current ecological mess. Of course I think a growing population is a big problem which needs continued efforts, but if we want to prevent catastrophic ecological crises in our lifetimes, we need to be well on the way to changing how much we consume by 2050. Mid-century is a milestone for many of our environmental systems. If current trends continue until then, we will have no wild vertebrates, or very few, on the planet, and likewise for insects. If we haven’t stopped emitting greenhouse gases by then, our climate will probably enter into a phase of runaway heating as permafrost melts and other natural systems release large amounts of carbon to the atmosphere. If we do not drastically reduce our consumption by 2050 there will be irreversible damage to our ancient ecosystems and it is likely that there will consequently be broad ranging wars over basic needs like fresh water. The fact of the matter is that we can’t reduce global population numbers by 2050 to meet these deadlines through reducing the birth rate. The only other population option is massive premature deaths, i.e. war, starvation, epidemics etc, which of course we hope to avoid.

What’s more, recent efforts to reduce population growth show us how untenable relying on population decline is. In the last few decades, there have been massive efforts to reduce global birthrates. And these have succeeded to a large degree, significantly reducing the birth rate to 2.37 children born per woman, as of 2014. But the global population is still rising. And even if we could achieve a stable growth pattern right not, reckoned to be 2.1 children per woman, by 2100 we’d only have reduced the global population by 10%. While such a reduction in the number of consumers would certainly reduce our destruction of nature it wouldn’t have hardly any effect on 2050 populations. What’s more, even the 10% reduction in 2100 isn’t enough to sustain human life at that point, all else being equal. If we look at eco-footprints, as the most widely known estimates of resources used, we see that our consumption is far above sustainable levels than the 10% reduction in population could buy us. The global average eco-footprints is in fact 1.7 times the capacity of the earth to replenish our fresh air and clean land. A 10% reduction in consumers, would only reduce our resource consumption by about 0.17 earths. We’d still be using 1.53 earths worth of resources, i.e. 50% more resources than the earth can supply without diminishing our life support systems. And this is assuming consumption rates per individual don’t increase over the next century, which of course they have been doing decade upon decade.

A more draconian restriction of only one child per woman, adopted globally and all else being the same, is probably impractical and ethically fraught. And, for the matter at hand, wouldn’t have much impact on global population by 2050 by which point we need to have turned off our destruction of the habitats that underpin all life. Of course over the long term one child per woman would have a dramatic effect on population and nearly halve global population by 2100. This would alleviate many of our environmental problems, provided, again, that we didn’t increase our consumption.

Birth rates in the industrialized world already fall below the replacement birth rate of 2.1 children per woman. There are 1.8 children born per woman in the US and 2.075 children per woman in the UK. Whereas in less affluent countries, birth rates reach up to 5 children per woman. Indeed, on there is a strong correlation between decreasing birthrates and a country’s GDP per capita. But the ecological impacts of those births are vastly different. While the average global citizen uses up 1.7 times their ‘fair share’ of earth’s resources, based on eco-footprint analyses, the average American uses 5 times their fair share, and the average Brit uses 4.8 times. If the next generation consumes at the same rate as their parents, then on average a Zambian’s 5 children will all together consume less than 1/3 of the amount that 2 kids in the US will. To square our current consumption with a fair share of earth’s resources by population alone, women in the US or UK would need to reduce their reproduction to 0.4 children per woman, or roughly 2 children for every 5 women. That’s not likely to happen. Although, there is a growing movement amongst the younger generation to not have children for this very reason.

So while reducing the global population is a good idea, those who are having the most kids are not those who are driving the destruction of our planet. It is those of us whose ecological footprints exceed our fair share who are the main problem. America and Britain, and indeed most of the industrialized world, are the glutinous and obese in terms of material consumption.

In the long term, funding birth control initiatives in less affluent countries is among the most cost effective ways a higher income country can act to reduce future environmental pressures. But reducing birth rates won’t avert the imminent climate change and biodiversity. To avoid these catastrophes affluent nations need to consume less. It can be difficult as an individual in one of these wealthier nations to reduce our ecological footprint to a sustainable level. I just calculated my COVID eco footprint and it is about 20% of the average American’s, primarily because of my very low meat / no dairy diet, but also because we have geothermal heating, don’t drive much, conserve energy and so forth. Even though this is below the global average, I still consume 60% more than my fair share. And not everyone will be willing or able to make environmental impact reduction the focus of their life. And thank goodness - I want people out there who grow organic food for me to buy, make beautiful music and art, who become doctors or engineers, and who work on civil rights to name a few lovely and important endeavors.

This is why it is important for all of us to send signals that we care about the environment to business, government and society whenever we can. Most effectively we can do this by reducing or eliminating our meat and dairy purchases. We can also buy less gasoline and less stuff, make consumer choices based on long lasting products, which are energy efficient, recyclable, and don’t have wasteful packaging. And so forth. And yes, it is ecologically responsible if we keep the number of kids we have to 2 or less, but that alone is not going to get us out of the mess we’re in.