We came, we saw, we conquered
Within a geological blink of an eye, our global population has expanded from maybe one or two million subsistence foragers to an astonishing 7.5 billion of the most environmentally intense creatures to have ever lived on this planet. Over the last forty years or so, we have wiped out about half of marine vertebrates, and nearly two-thirds of land-based wildlife. Human beings and our livestock now comprise the vast majority of the Earth’s land mammals by weight. We are on route to hit 11 billion around 2086 and to keep on growing well into the 22nd century, with no end in sight.
What should we make of this astonishing expansion of human demands upon our planet? Apparently, we should not worry. We will figure something out; technology will save us. We have been able to crank up food production in the past, so it should be no problem to do that again and again. Soon automation will free most of us from the toil of work and enable us to spend our days playing online video games, arguing on social media, or binging on Netflix.
This all fits with a story we like to tell about ourselves. Let us call it the “humans are exceptional” narrative. It says, we are not like other animals. We are very, very smart creatures. There are no problems that human ingenuity cannot fix, and virtually no resource constraints that we cannot work around. Societal progress is inevitable and one-directional. We are destined for big things, to live large – in every which way. Maybe we will go on to colonise other solar systems, or abandon our pesky biological bodies altogether as we transcend into an all-brain lifestyle. This is not to say that we are safe from catastrophic risks, of course. Earth could be hit by a comet or asteroid, or engulfed in a sudden, technology-frying solar storm. Humanity could prove too smart for its own good, developing advanced technologies that unleash powers we cannot control – from God-like AI that runs amok, to lab-engineered pandemics, to killer bots and 3D-printed guns, to good ol’ nuclear weapons.
It’s quite an exciting (and flattering) story, even if it could all end with a bang.
There is another, much less appealing way of looking at things. Let us call it the “humans are still animals” perspective. Instead of tantalising possibilities, it is a story of disquieting probabilities.
Not with a bang, but a whimper
Our population trajectory looks unnervingly like the trajectory of a run-of-the-mill mammal population living free from predatory pressures.
It looks like overpopulation.
What population size is sustainable? It is impossible to draw a precise line, or determine when exactly we crossed it. But we can look at the symptoms. One of the most serious is climate change, which is primarily driven by population growth (along with economic growth). But there are many others, including overfishing, freshwater scarcity, deforestation and species loss.
Now, techno-optimists, cornucopians and other growthists may protest that people are living better than ever today. This much is true. There have been many famines, and the number of people going hungry has not changed very much – still hovering at near one billion. But billions of extra people have been added to our numbers and are getting enough to eat. Hundreds of millions are enjoying more comfortable lives than they used to, and technology truly has improved people’s lives in a multitude of ways.
What is the problem, then? Well, say I had only a £1,000 to last me one month, and I chose to blow it all over a weekend. It might be strictly accurate to describe me as financially comfortable, or flush with cash, during those two days of reckless overspending. And yet, it would be deeply misleading. When thinking about overpopulation, the question is not whether we are living well, but whether we are living within our means, now and in the foreseeable future.
Like all animals, we ultimately depend on natural resources. There is only so much arable land around the world, and only so much edible matter that plants can produce even with the best conditions. We have been using a suite of very useful technological hacks - fertilisers, high-yield crop strains, pesticides, and irrigation - to extract far more food than can be produced with natural sources of plant nutrition. Even then, there are limits, and those limits are shrinking, not rising. The same intensive farming that has allowed our enormous population to fill their bellies is damaging our ability to grow food, by degrading and depleting already scarce soil and water resources and by contributing about 25% of total greenhouse gas emissions. The FAO estimates that soil erosion alone is knocking off 0.3% of annual crop yield each year; at this rate, we will have lost 10% of soil productivity by 2050. Global warming is expected to knock off an additional 10% during that time. A 20% drop in productivity may sound manageable, but let us not forget: by then, we will have two billion more mouths to feed, equivalent to the entire global population when David Attenborough was an infant.
Looking further ahead to the end of the century, and on current trends, the yield of such staple crops such as wheat, rice, and maize could be halved. This would have catastrophic consequences for a human population that will likely be 50% larger by then. Of course, we cannot rule out that advances in (for example) genetic engineering could lead to crops that are better able to withstand a warmer, more erratic climate system. But realistically, technology cannot give us crops that will survive extended droughts, flooding, or being uprooted by tropical storms. This is all grim enough, but there is more. On current trends, vast tracts of the planet are set to become uninhabitable, either too hot for humans (and most animals) to withstand, or else swallowed by rising sea levels, causing mass displacement and human misery on a scale that is difficult to contemplate. This is not a remote future we are talking about. On current life expectancy trends, we can reasonably expect that many people who are children or teens now will still be alive in 2100, elderly denizens of a chaotic, hungry world of more than 11 billion people.
Apocalyptic blindness, and doing the right thing
Of course, it may be that things will turn out all right somehow. But this doesn’t mean that what we are collectively doing to ourselves and to future generations is in the least bit justifiable. These are catastrophic risks we are talking about, risks which could be avoided, not by complicated technology, but by embracing an ethos of reproductive restraint. Instead, we seem to be as committed as ever to a primitive, pro-natalist ideology that privileges prospective parents’ procreative freedom and the sheer expansion of our numbers over virtually any human interest or requirement of justice.
It doesn’t help that overpopulation intersects so neatly with our weaknesses. For all our braininess, we humans are notoriously liable to systematic failures of rationality. We struggle to think about the future, to weigh up probabilities, assess risk, estimate payoffs, and to respond appropriately. These weaknesses extend to moral reasoning. We find it difficult to care about the wellbeing of people we cannot see or identify, such as those who live far away, or not yet born. To top it off, there is so much complexity and interconnectedness in our world that most of us have lost sight of just how dependant we are on natural systems. These factors combine to produce what the philosopher Günther Anders has termed “apocalyptic blindness”. We just cannot face the possibility of a bad ending to our story.
But maybe we can reconcile the two narratives. Modern birth control methods are a real triumph of technology: safe, effective, and inexpensive. Access to modern contraception allows us a degree of control of our own bodies that truly does set us apart from other animals. In much of the world, though, there are still cultural or religious obstacles to using birth control, even where it is available and even for people who do not particularly want to have children. In addition, many, many people around the world do still want a large family.
A concerted effort to change social norms and access to contraception could make a huge difference to how things pan out for humanity over coming decades. This is illustrated by the UN’s “high” and “low” variants, which only differ from the medium variant in assuming family sizes stay half a child larger, or smaller (respectively) over the period projected. By 2100, the “low” variant produces a population of 7.3 billion, whereas the “high” variant yields a population of 16.5 billion, a difference of 9 billion.
If we truly are the exceptional, highly intelligent species we like to think we are, then we must abandon outdated ways of thinking about parenthood and children that emphasise parental entitlement and tradition at the expense of the life chances of prospective children – and everyone else’s.
HuffPost UK Tech has launched HuffPost-Apocalypse, a project that aims to investigate what an apocalypse would mean for humanity, how we can best delay the end of the world, what the world will look like after we’re gone and what the best viable options for survival will be for anyone left. Join in the conversation with #HuffPostApocalypse on Twitter. To read more from the series, visit our dedicated page.