This may come as a surprise, but people are capable of holding unsupported notions…unexamined beliefs and expectations. A common default assumption—often quite reasonable—is that conditions will continue in a fashion that is recognizably similar to the way they have been during one’s lifetime. Suggestions to the contrary tend to be met with suspicion—or even hostility in the case that the suggested outcome is less than rosy.
What if we presented possible options for future human developments—let’s say human population as a solid example—and pretend it’s a menu from which we get to choose. What outcome would most people see as the desired goal? What would make them happy, or satisfied? Which population curve below do you think most would select?
I present the following options:
A: Indefinite exponential rise. This implies no biophysical limits, ultimately demanding expansion to space (as if possible).
B: Moderation into a linear rising state, allowing continued growth but not in crazy-pants fashion.
C: Logistic leveling: no drama: we found our place and aimed right for it with no corrections—like it was meant to be and we knew what we were doing all along.
D: Peak and modest decline to some medium and stable value, indicating a slight boo-boo (overshoot) in our trajectory.
E: Peak and substantial fall to a vastly smaller population before stabilizing. In this case, we had it dramatically wrong in a massive overshoot.
F: A post-peak crash to zero (i.e., extinction; could be due to ecological collapse, nuclear annihilation, sex robots, or classic evolutionary failure of our species).
Now picture yourself and a bunch of others sitting around a table at a restaurant holding this menu and trying to decide on the future. What are you having?
Process of Elimination?
Ha! I tricked you all! I would claim it’s not an open choice! It will be no surprise that I rule out option A. Exponentials fail, and juvenile space fantasies aren’t coming to the rescue. Even then, good luck maintaining an exponential against the cruel realities of expansive space! “I’m sorry sir, the kitchen informs me that this option is not available (and never has been).”
Option B also ignores biophysical limits, in that growth of any form is not a long-term realistic prospect, even if not disastrously exponential. Also unavailable from the kitchen.
I suspect many people in our society would pick option C. Looks tasty. This is the dream scenario: we figure out how to live on the planet and smoothly cruise into stability without any obvious sacrifice, then hold it there indefinitely as human civilization flourishes. Except: the scale of today’s activity on the planet far exceeds the community of life’s capacity to survive. Not only would the sixth mass extinction stay on track, but we have zero realistic all-things-considered plans for maintaining high-throughput modernity at the ten-billion person scale. From agriculture to energy to materials (upon which which energy conversion depends), we don’t know how this could possibly work for centuries or millennia. There’s no credible plan. Another note is that real populations seldom follow the no-drama logistic curve. Treat it as a fantasy, and try to ignore the appeal. You’re probably beginning to dislike this restaurant, for its lack of actual choice.
Option D is the first to acknowledge overshoot. I suspect the chef will get a smattering of orders from this category, just like the gluten-free, dairy-free “pizza” that’s on the menu for the rare bird who needs to go that way. This option admits defeat, of sorts. It acknowledges that we’ve gone too far already and need to dial things back in order to carry on. In spirit, I am on board. But if our current attack on the planet is at the level of rapidly initiating a sixth mass extinction, is a factor-of-two moderation nearly enough to tip the scales? “I’ll check with the kitchen—I’m uncertain whether this dish is available today.”
Option E is qualitatively similar to Option D, but quantitatively differs in that the ultimate steady-state level is vastly lower than the peak. This is not a small factor-of-two correction, but an order-of-magnitude or more. It’s the shoe leather option on the menu. Why would anyone ever pick this one? Well, if the other items are truly unavailable… This might be the only way to survive, by the dictates of evolution, ecology, and biophysics. The kitchen can probably oblige and rustle something up. Why is the chef now walking around bare-footed? Serving suggestion: goes down better with ketchup.
Option F is implicitly on the menu, folks. Dismayed by the lack of acceptable choices, we could refuse to order any of the unsavory options, insist on “living large,” and consequently end up starving ourselves in pointless protest.
Grade Analogy
I also like a grade parallel here. Students might desire an A or B, but can live with a C as a passing grade. D is effectively failure, and F is unambiguous failure. That leaves E: an obscure grade that is off our radar (outside Hogwarts). But we need to think out of the box here and accept that we are heading toward uncharted territory, for which we do not yet have set associations. If my choices are E or F, I might as well try this E-thing, which might turn out to exceed expectations.
Happiness?
This post was motivated by a discussion I had with a sharp friend about the path of humanity. I was making the point, unsurprisingly, that modernity is a temporary aberration that will not be ecologically supported for very long. He rejected the idea of any future path that had even a whiff of hunter-gatherer lifestyles, adding something to this effect:
Look: all you have to know to appreciate that human life was miserable in the distant past is that population was held down by external factors. Life was tough [nasty, brutish, short was the gist].
This is very illuminating. When I responded: “Ah, so the only mode of existence compatible with human happiness is unbounded, exponential growth?” it was immediately clear to him the pile he had just stepped in.
But this is the crux of the matter, and worthy of serious consideration. If the only way for humans to be happy (not miserable) is in a world without limits…well then we’ve come to the wrong shop, folks. If defiance of biophysical reality is necessary for us to be the transcendent, liberated former-animals we think ourselves to be, then I’ve got some bad news. Pinocchio will never be a real boy. Translation: our artificial construct of modernity will never have a permanent, integrated place within an ecological context.
Back to the Menu
Now let’s return to our menu. When presented in this way, I think logic circuits kick in so that most people—I hope—would recognize option A (indefinite exponential growth) as not being possible (otherwise it might seem the happiest choice). Once in this mindset, option B might also be apparent as untenable, and that’s certainly progress. If I am correct to suspect that option C would be most popular, aren’t we back to the “miserable” state of imposed limits?
I think the difference is that to most people, the target steady-state population is our choice—not nature’s choice—in which we have two kids on average, medically-enabled longevity, technological goodies, and opera. This is the “arrived” notion: under our control. What seems to be objectionable is when ecological realities are dictating the terms. Two things: first, ecological realities probably remove option C as being unsupportable to begin with; second, even option C is ultimately limited by biophysical reality, in that births are still constrained (restricted, independent of happiness/desire) and deaths still motor on. Population trajectories are all about biophysical realities of birth and death, so that any steady solution goes hand-in-hand with limits on the biophysical front. To maintain steady state, increasing longevity would have to be accompanied by a reduction in births. We can’t just do whatever we want.
I’ll make one other point with regard to my friend’s “misery” statement. It implies that every other species on the planet—constrained as they are by external factors beyond their control—must lead miserable lives, and that happiness rests on control. What a depressing mindset to hold about our glorious planet of life! I reject the notion that squirrels are miserable, or that early humans were miserable—and frightened—much of the time (see next week’s post). I take that attitude to be projection of our own unfamiliarity and fear over the prospect of losing the infantilizing influence of modernity. I have enough respect for early humans to believe that they faced challenges with grit and equanimity, while finding it within themselves to laugh, joke, tease, sing, and dance.
Overall Lesson
The point of this exercise is that not every drawing we could slap on paper is biophysically, ecologically supportable. In fact, the vast majority are not. It is probably approximately true that the area under the curve—above a certain threshold of sustainable population—is limited, as excess/overshoot leads to accumulating ecological damage, and an initially-healthy Earth can only take so much. This precludes, for instance, the pleasant notion of an arbitrarily gradual decline toward sustainable levels. Gotta keep the area below the breaking point. We can’t just do anything we wish. Does that lack of control commit us to misery? Careful: this is a tantrum-free zone.
Even in a deterministic mindset, where the ultimate answer is inevitable, the result is utterly unpredictable to us. Options E and F, for instance, both seem to be on the table, and I would rather that our species survives beyond the modernity episode than execute its extinction as a result of clinging to the colossal mistake of modernity for too long.
That means, if option F is to be avoided, steps must be taken to set us on the path of option E. Efforts in that direction come with no guarantees, but failure to make the attempt is far less likely to end up there.
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I have to reject your friend's statement that 'human life was miserable in the distant past.' First off, how can this be known? The 'miserable caveman' image is a modern construct. Yes, life was harder in many ways. But was it unfullfilling? Is life somehow 'better' today? When hominids walked the earth for a million years, were they all miserable before modernity emerged? Seems nonsensical to me. Also, like you, I think that if happiness requires some sort of control, then we are forever doomed to perpetual gloom. In my mind, 'control' is somewhat akin to 'desire,' and to me, this is the source of our misery. I paraphrase here supreme pessimist, Schopenhauer, writing in, On The Vanity of Existence: "It seems we find fulfillment only when we are striving for something; but as we have seen, these things for which we strive fail to satisfy, are mirages which fade when we reach them." It's a Hobson's Choice: menu item "E" is our only real option. So let's find ways to accept and adjust to it.
I've read/heard multiple times that once we got past the juggernaut of infant mortality, many people lived to be old. And we've seen evidence from the beautiful art created on cave walls that life was not just one long stream of misery.
Of course, that was humans living in an incredibly rich world, ecologically speaking. That world is gone now. If we get E rather than F, it could be that the few humans left really will live in absolute misery, given the scorched Earth we are leaving behind. Knowing that, would we still choose E over F? I'm not so sure.
Next week's post will contain more detail than anybody probably wants on life expectancy as a function of age for hunter-gatherers. And you're right: plenty of old people around (not at all rare).
>>that was humans living in an incredibly rich world, ecologically speaking. That world is gone now. If we get E rather than F, it could be that the few humans left really will live in absolute misery, given the scorched Earth we are leaving behind. Knowing that, would we still choose E over F? I'm not so sure.
I agree. For me, I would prefer death. Possibly non-violent.
This thread has taken a dark turn! Admittedly, the multitude of us who depend on grocery stores and the like would face serious challenges. Those who are born later will fare progressively better, knowing only the new ways and benefiting from those who came before and figured some things out on the fly. But it does not need to be (and will not be) a monolithic decision or process. People come in different flavors. Those who strive to survive will do their best and content themselves with anything but F.
Just look at photos of chimpanzees grooming each other. They seem to be content with life most of the time. We don't need all this fancy crap to be happy. We just need to hang on to enough scientific knowledge to be able to keep child, infant, and maternal death rates low. If we can do that, we will probably have a lot more fun in our lives after modernity ends. If you look at depression rates in industrial societies, it's pretty clear smart phones don't produce happiness.
"We just need to hang on to enough scientific knowledge to be able to keep child, infant, and maternal death rates low."
I don't think that's on the menu. Or at least, the kitchen can't supply that item.
This wish is yet another example of us wanting to be in control and everlasting.
Consider what this takes away from us, besides the grief of the loss of a loved one: evolution itself.
Our modernity has made it so that just about anyone can live to reproduction age, and to pass along whatever genes might have caused their demise prior to procreation.
Evolution requires: 1) random mutation, 2) selection, and 3) heritability.
We have effectively removed selection pressure, outside of a tiny number of really dire mutations. This does not seem like a good idea!
You said sometime back …accepting the death of modernity is—to me—not that different from accepting my own death…
Facing either of them is easy.
My wife and I are seventy-six and did interesting chemical research until last year. If both of us are about to meet death we will happily cling to each other and go down. But, before the actual end, during the coming years – hopefully no longer than a decade – we have to endure our body parts slowly withering one by one. The process has already started. This is the hard part.
That is why, 'for most people it is easier to visualize the end of humanity than facing the end of capitalism (modernity).'
We, mostly you, have to think of ways to lose the modern modes of happiness one by one while maintaining our emotional balance.
It is possible that the spirit of my comment was not clear, because I agree that both are easy and unstoppable (so why whine about it?). And yes, a giant part of my message is exactly that we need to find other sources of meaning, as modernity won't cut it. The tail end of my Metastatic Modernity series was about walking away and letting go.
"steps must be taken to set us on the path of option E."
Do you really think humans can control how they act to consciously go down a particular path?
I think that the realisation of free will being an illusion might make us also realise that we don't have the ability to choose the path of our species (and that path's effect on other species). It's hard to see humans settling into some climax ecosystem, in the future, where no group of them think of ways to make their lives "better." So the only two options I can see are F or a continual repetition of E.
The way I put it is a sort of tautology. If we end up on E and not F, that path must have a causal history. Or in other words, the causal histories that lead to E and F presumably have differences, so that steps leading to E involve human actions—witting or not. Animals react to stimuli, if they are perceptive to the stimuli. Hypothetically, if enough people are aware of the perils of outcome F, they might just respond in ways to avert such a fate. We all elect paths (or our atoms/neurons do, presented with an array of inputs), but we're generally not able to predict consequences very well. Here's a deterministic way to put it: whatever path unfolds, it will involve people (and other agents) taking steps along the path, having processed optional responses given the available stimuli. We just don't know what path. I don't see E repeating, given the one-time elements that let this happen (stable Holocene; surface ores; intact forests and soils; fossil fuels—all gone after this round).
87 billion tons of metric tons of proven iron reserves/2 billion years = ~45 metric tons per year; 1.6 trillion barrels of oil /2 billion years =~800 barrels per year for all humanity. I'd rather have a very small order, use it wisely and leave the rest for future generations to use it wiser. Deeper ores can be extracted at a faster rate closer to the time the sun swallows the earth (nothing to lose). Just curious on what your students think about our future. Our physics professor covered some of those topics during his intro classes 30 years ago, we were startled and when we asked him about solutions, he said "you're all smarter than me, you will figure it out… my salary is less than $50 a month and I don't take the elevator".
"87 billion tons of metric tons of proven iron reserves/2 billion years = ~45 metric tons per year; 1.6 trillion barrels of oil /2 billion years =~800 barrels per year for all humanity."
It seems to me that you may not be familiar with the "low-hanging fruit" principle.
The remaining iron ore is not sitting on the surface of the Earth. Future humans in Scenario E won't be able to just poke a hole in the ground and get at the remaining oil.
The late Howard Odum taught us that technology is simply a form of embedded energy. With the "low-hanging fruit" gone, humans will not have the technology necessary to go after those juicy apples at the very top of the tree.
Yes, that's a good way to put it. I try to hope similar paths, where if enough people become aware of the default path we seem to be on, they might be able to enact a low suffering way down.
If F doesn't happen, I do see E repeating, though not to the same peak and maybe not modernity as we know it, but there have been other civilisations, in the past, which may enable a rise in population for a while, after a long (deep) time. If fertility recovers.
Future peaks: very likely. But much smaller scale and less likely to be global. I think.
As Douglas Adams put it “man had always assumed that he was more intelligent than dolphins because he had achieved so much—the wheel, New York, wars and so on—whilst all the dolphins had ever done was muck about in the water having a good time. But conversely, the dolphins had always believed that they were far more intelligent than man—for precisely the same reasons.”
The basic premise of your discussion is demonstrably wrong. Aboriginal societies the world over enjoy plenty of happiness. Mankind can be happy without smartphones and intercontinental vacationing. We can be happy even in the face of high mortality. There is nothing fundamentally necessary in our current ‘civilised’ lifestyles.
I agree whole-heartedly (maybe it doesn't come across in this post, but does in others). Maybe the distractor is that I am trying to anticipate how typical members of our culture react to the choices and work to reset expectations. I, for one, am certain that modernity is not necessary for happiness, and in the end is the worst thing for it (given the enormous scale of suffering it has and will cause).
I don't recall how Richard Dawkins put it in his book, The Greatest Show on Earth, but it was something like, life is harsh. Without medical intervention, most animals would perish from predation, starvation, injury or illness, with all of those being potentially painful. That's just the way it is. Of course, some of the time alive can be content, even happy. In The Old Way, by Elizabeth Marshall Thomas, those living the way people lived thousands of years earlier had good times and bad times, while they were alive. But we've been used to comfort and medical interventions. The latter won't be available and the former will not be anything like we're used to. But it will all be normal life for humans in the future and they won't have anything to compare it against, so they'll be happy in their own way. The Old Way.
"we've been used to comfort and medical interventions."
And yet, many of those "medical interventions" are necessary precisely due to our modernity!
Fast food and highly processed food — both, aspects of modernity — are arguably killing us. As is our sedentary life-style — sitting is the new smoking.
As a "leading indicator" of Scenarios D through F, there is evidence that the average human lifespan is now declining, for the first time since the widespread exploitation of fossil sunlight.
US longevity plateaued in about 2013, peaked in 2015, and has been steadily declining since then — even post-COVID. It appears that most of these "excess deaths" are from life-style choices. Which can be said of Scenario F, as well.
I think it's embedded in human nature to be in constant adaptation and to the extent of each individual possibilities to plan over a "reasonably" limited timespan ranging to the amount of time they feel enough confident about the information they have to take specific action (in many times just preventive – the farthest in time the more open to recalibration -, very often blissfully assuming over-optimistic scenarios) while (if they are enough caring and responsible as parents) trying to make sure that their offspring will be properly able to adapt and therefore plan accordingly for the next iteration given the information they'll have and boundary conditions they may face. The problem is when there is a huge misunderstanding and distortion of reality due to system-promoted ignorance at an individual level concering our own limits and the levers of significative meaningful control over the direction of the ever energy-hungry societies we live in have ended up in hands of narcissistic, demagogic, egocentric sociopaths that took/cling onto power for their own personal benefit and that steer the discussion over our future in a delusional way. (if they are not too busy dealing with self-sustaining themselves in power)
Life is definitely worth to be lived without the perks of modernity (let alone its disadvantages) and in spite of the turmoil that will follow to the unavoidable collapse due to the multi-scale overshoot we have triggered I'd go for E with the little sachets of ketchup I may scramble around in the aftermath :p
Thanks a lot for your work Tom, it's a delight to see how with your posts you eloquently go through the entangled weeds of modernity with great humility. Most comments here are also very insightful and provide me with great input to think about in the ceaseless quest to better understand all what surrounds us (and trying to change some minds about my humble perspective along the way as better as I can) given ones limitations.
Cheers from Spain, may all of you have a great day!
C and D are no longer on the menu (perhaps they were, once). However big a mess civilization makes, there are bound to be *some* survivors, which leaves E as the most likely scenario.
"I think that the realisation of free will being an illusion might make us also realise [that we have no capacity to choose]"
Circular reasoning is [a] defect in an argument whereby the premises are just as much in need of proof or evidence as the conclusion. [It] is often of the form: "A is true because B is true; B is true because A is true." https://en.wikipedia.org/wiki/Circular_reasoning
Humans lived for millions of years without destroying their surroundings, before greed took over.
The fact that we are animals means we are evolved to live on the Earth (of course extinction can't be ruled out, as with any given species).
"[Man] is habituated to idleness, and to contempt for all the products of labour: is taught to spoil, throw away, and again procure for money anything he fancies, without a thought of how things are made" – Leo Tolstoy.
Far from being inevitably repeated, modernity and its wasteful ways are an anomaly.
Sometimes another way to say "circular reasoning" is "self-consistent," which is okay. Some things just are. We posit the existence of electrons because we see them. And we see them because the are. We can't logic electrons into existence by mere thought, as our brains do not create external reality. Sometimes things that look like circular logic merely capture a self-consistent mental model of something that just IS. Doesn't make it always right, but it's not the sin some paint it to be, to me, anyway.
The fact that humans lived for millions of years without destroying their surroundings is a function of the number of humans. Even Homo sapiens lived for hundreds of thousands of years without destroying their environment because they moved from time to time, allowing that environment to recover, apart from the mega fauna that they had exterminated.
Tom gave a great answer on the circular reasoning bit. I realise it is circular but it's easy to forget that we have no free will and so it's easy to think that humans have a choice on which path they take.
"The fact that humans lived for millions of years without destroying their surroundings is a function of the number of humans"
Yes, and the number of humans is a function of the destructive system (modernity) we live under. Obviously the human population is too high, now. Without modernity, that number will plummet.
Humans of 10,000+ years ago proved they could live, greed-free, in relative harmony with Nature.
It was done then, it can be done again.
"it's easy to think that humans have a choice on which path they take"
It is – because it's true. Tom said as much, himself: "if enough people are aware of the perils of outcome F, they might just respond in ways to avert such a fate"
And, whatever happens "it will involve people (and other agents) taking steps along the path, having processed optional responses given the available stimuli" – i.e. it will involve choices.
Sadly, that people lived 10,000 years ago in "relative harmony with Nature" only proves they can do that for some period of time. Clearly, that way of living failed to continue, thus proving that they can't do that over deep time (let's say, sustainably). Even humans that did live in apparent harmony, wiped out mega-fauna and used tools to given them an advantage over other animals, including other apes.
No species voluntarily limits the resources they consume, the limits happen due to environmental factors. Once people discover how to usurp those factors, for a while, they will do so. We have the proof, from our history.
I think Tom explained that the "choices" are an illusion but that the choices we appear to make are a consequence of our experiences and our genes. So it may be (no stronger than that) that if enough people become aware of what is happening, enough people may start to make different "choices" that are less detrimental to the planet's ecologies. I hope so though have no expectations on that score.
"that way of living failed to continue, thus proving that they can't do that over deep time"
I reckon living for millions of years in *relative* harmony with Nature qualifies as sustainable.
"No species voluntarily limits the resources they consume"
Except many humans have done exactly that. Australian Aborigines are an example that comes to mind, also Native Americans, to some extent. Smart enough to realise that such supposedly unnatural behaviour is actually in their best interests.
Humans' usurping (of environmental constraints) has a cause: greed. Failure to admit this, amounts to letting the usurpers (who've only gotten worse) off the hook.
The era of greed (aka modernity) can be looked at as a mis-step, in the same way that viewing the Earth as flat, or as being the centre of the universe was. It's not an inevitable trait. Humans are adaptable, and so are their beliefs.
Of course experiences and genes, aka nature and nurture, inform all behaviour, but that doesn't mean choices (no quote marks) aren't made.
Otherwise, why even bother positing an argument? Clearly, one only does so in order to try to persaude others of its merit. Are you open to changing your mind in the light of evidence or debate? If the answer is yes, then that means you admit that you are able to choose between two positions.
The term 'free will' is unfashionable – that's ok, don't use it.
"living for millions of years in *relative* harmony with Nature qualifies as sustainable"
Maybe, but no human species has done that.
"Australian Aborigines are an example"
Yet they did a lot of damage to their environment. But a group of humans isn't the human species. We've seen group after group of primitive groups succumb to "civilisation" practiced by other groups. This just shows that, eventually, unsustainable ways are more attractive or provide an advantage over those trying to live sustainably.
Choice is an illusion (research has shown that choices are made before our conscious brain becomes aware of that choice). You ask "why bother" but, in fact, we don't bother. We just do. We act like a species.
Yes, I'm reminded of the common phrase:
If it walk like a duck and quacks like a duck, it's an illusion of a duck.
>["Look: all you have to know to appreciate that human life was miserable in the distant past is that population was held down by external factors. Life was tough [nasty, brutish, short was the gist]."
That's repeated by and large but not backed by fact though, just a repeated trope ? Like the one about modernity. I can think of two examples but perhaps because I am not widely read in anthropology, I am going to suppose there are a plethora of other examples. Dave Graeber for example in Debt: The first 5000 years and the second any one of a number of studies like this one
https://aeon.co/essays/why-inequality-bothers-people-more-than-poverty
>Most remarkably, his research revealed that the Ju/’hoansi managed this on the basis of little more than 15 hours’ work per week. On the strength of this finding, the anthropologist Marshall Sahlins in Stone Age Economics (1972) renamed hunter-gatherers ‘the original affluent society’.
@Tom Murphy.
First time commenter on your blog, though I do keep half an eye on your posts.
Slightly off topic but related to your posts on population………
If the present futility rate is 2.1, how does this change if the unwinding of modernity effects health care?
If childbirth and infant mortality rates return to pre- industrial level (as well as female mortality rates giving birth) , what sort of figure are we looking at above the present 2.1?
Population decline could accelerate as the required fertility rate to maintain the population keeps going up, adding the the overall decline.
Often pass on off-topic posts, but this anticipates a post next week. 2.07 is replacement if NO mortality (just accounts for male/female asymmetry), which is effectively what affluent countries experience (2.1). Globally, the replacement at current mortality is around 2.3. Hunter-gatherer life expectancy curves push replacement fertility to around 4. So, yes: it is a function of health care, and yes: expect these to be moving targets during a major transition.
In my poorly reseached opinion, I don't think that humanity is even remotely close to having the power to extinguish itself. People who argue so often do so in within the "anything is possible" framework of modern thought that vastly overestimates the capabilities of human civilization. While modernity is plenty capable of inflicting significant pain in the ecosystem it seems hard to believe it won't destroy itself before destroying the last human. Humans have survived far worse conditions along the ages. If humanity is to become extinct I predict it will happen due to some seemingly random natural event completely outside of our control.
I tend to agree that humans won't go extinct, because the menace of modernity will fail before doing us all in. However, the plausible scenario is that a sixth mass extinction is initiated by modernity, via habitat destruction, climate change, toxic "forever" chemicals, etc. When things get weird, we could unleash another wave of destruction as we cut forests and hungrily hunt down everything larger than a mouse. A sixth mass extinction could avalanche on its own momentum well after modernity has folded. Humans, as large, hungry, high-maintenance mammals are unlikely to survive a mass extinction (defined as losing at least 75% of species).
Barring that sort of ecological collapse, I think humans will continue living on the planet, differently. But we sadly cannot rule out ecological collapse, which can be a self-reinforcing, cascading event once below critical integrity (possibly there already: can't prove we're not; the story is in progress and tanking fast, yet still takes time to fully play out).
The new Living Planet report says "Global wildlife populations have plunged by an average of 73% in 50 years, a new scientific assessment has found, as humans continue to push ecosystems to the brink of collapse."
95% decline in Latin America during that time. Lower declines in Europe and N. America, but only because the majority of destruction happened before 1970 so there's less left to destroy.
I'm not sure how we can look at these numbers and say we're not utterly fragmenting the web of life.
At the very bottom of the food chain, I watched a heartbreaking video recently by Dr. Richard Kirby showing plastic pollution and plankton. The plankton attempt to eat the plastic and choke and die. Or they get entangled in the plastic and die. We are destroying the web of life from the top down and the bottom up, the largest animals and the tiniest animals and everything in between. I don't see how the vast majority of humans would survive the wreckage we are leaving behind. As you've said, most if not all large mammals will not make it through the sixth mass extinction.
Link to video if you want your heart broken: https://vimeo.com/879043656
Link to article about 73% decline in just 50 years if you want it broken again: https://www.theguardian.com/environment/2024/oct/10/collapsing-wildlife-populations-points-no-return-living-planet-report-wwf-zsl-warns
@João Oliveira
I think the folks on the Andaman Islands will be just fine when modernity ends for the rest of us.
I'm greedy and want a seventh option! Particularly, halfway in between D and E. Let's say a decline to 1-2B people. While a stretch this seems like an outcome that I can imagine a plausible path to without apocalyptic conditions.
The path I'm imagining is: birth rates start declining a bit faster and human population peaks at about 9.5B. By 2100 the average fertility rate is 1.7 and dropping fast. Europe, Americas and Asia have all roughly stabilized at 1-1.3 and Africa is quickly joining them. As climate change worsens and the number of people is still quite large, the birth rates only continuing to trend down. It isn't until 2150 that the population has dropped noticeably to 7-8B. Between supporting their parents and dealing with the worsening world the birth rate continued to decline and stands at 1.4. I haven't done the math out exactly, but I think roughly it would only take 3 generations of this for the implied steady state global population to be
Uh oh. You're ordering off the menu? At an establishment that has already indicated that almost none of the items even on the menu are unavailable? Is the customer always right?
We can't always get what we want. While we could all draw/imagine a diagram following the curve you suggest, that's not the hard part. The hard part is what happens to Earth if it takes until 2200 to get down to even 2B. As I suggest in the post, the area under the curve measures the amount of damage/destruction, and some costs are unaffordable (e.g., via sixth mass extinction). This is not a mad-lib choose your own adventure scenario, but a severely biophysically, ecologically constrained situation. The post asks if we can cope with a reality that may not be to our liking—the suggestion that we bow to nature rather than the other way around.
Tom, you refer to the area undrr the graph measuring the cumulative destruction wrought by modernity. I agree, although there is, of course, a population level (in conjunction with a corresponding low impact lifestyle) below which there is no destruction. It is possible that a permaculture gardening/ regenerative herding based civilisation could support a fairly high population using manual labour and simple hand tools. This needn't be a terrible option for the planet. Such systems support high levels of biodiversity, albeit altered from the "natural" alternative.
The wild areas of my farm mainly grow thorn trees and brambles, whereas my garden and likewise my grazing land support a high diversity of flowering plants, which in turn supports a different, but not necessarily lower caste of wild creatures. The broadacre cropland, on the other hand, is pretty barren, despite being organicly farmed.
I did mention this "above some baseline" concept in the post when talking about the area under the curve. One might take it to be whatever steady-state population is ecologically possible in Option E. The real world is trickier than that simplistic model, but it captures the idea. I'm not qualified (is anyone?) to speculate accurately as to whether permaculture works long term (100,000 years or more) in ecological balance. We only know that hunter-gatherer does. I worry a little about the psychology of a species exerting this level of control over its environment, playing gods. But I can't rule it out.
A few days ago, I heard a story on the radio about ants farming fungus. Apparently, ants have been farming fungus for millions of years (i.e. they have done so in a way that is integrated with the rest of the community of life).
https://en.wikipedia.org/wiki/Fungus-growing_ants
Right; Lisi Krall has a book called Bitter Harvest that describes the parallels (and differences) in agricultural systems across species. A big distinction comes in grain agriculture (allowing dry storage), and also in genetic vs. cultural evolution—the former being slow enough for the ecological community to track and accommodate the novel mode. Yet, agricultural insects do exercise a degree of separateness from their environment, and also establish hierarchies and division of labor in similar ways to what our agricultural systems promoted.
I am sure you will get some pushback that overpopulation is not really the problem. However, for another angle on the population crisis that accelerated greatly since 1970, consider the following. The population right now is 8.182 billion. At a 2000 kcal/day/ca diet, the heat produced from consuming this food is 68.46 million gigajoules every day. At 6.12 gigajoules per barrel of oil, this is equivalent to the heat produced by burning 11.19 million barrels of oil – every day. The oil production of Russia is 11.26 million barrels per day. In other words, the mass of humans on this planet emits about as much heat every day as the daily oil production of Russia. This is a significant source of heat that changes the climate. It is not just about global carbon emissions. It is also about heat and entropy.
It is illuminating to view your graphics. But it still comes down to, "Live simply so others can simply live." Growing your own food is part of this. And of course, giving your surplus food to your neighbors is pretty simple. One can even promote a gift economy on a local scale, which I have been doing for the last two decades. For more on the gift economy, see The Gift by Marcel Mauss (1925).
In the short term (say, the next 200 years or so), I think F is just as unlikely as A. In the long term though, it's probably impossible to predict what a 6th mass extinction might culminate into. Species have gone extinct before, so why not homo sapiens? I wonder however whether cultural evolution might make homo sapiens more adaptable and therefore more resilient even in the worst-case scenario. Of course, sudden and massive population contraction is a form of adaptation, just not the kind of adaptation we like and therefore more likely to be forced on us than actually chosen.
I like your work, Tom. I happen to run a podcast about climate change and our energy future (I live in Iceland and the audience is mostly Icelandic). Would you be willing to join me for an interview where we can discuss those issues?
If we "succeed" in a genuine sixth mass extinction (at least 75% of species wiped out), then as large, hungry, high-maintenance mammals, I would place high odds on that outcome directly translating to graph F for humans. I have little faith in cultural tricks resisting this sort of tidal wave.
Tom,
A very nice write up. I think the more likely scenario is E, but there is some possibility of scenario F over the next thousand years. However I think the decay part of scenario E is too smooth. It’s likely to have a series of abrupt drops in population due to crisis such as war and mass breakdown in trade with periods of steady state population with only slight declines. Although I won’t be alive to see it I wonder what the population pulse half height width will be, 100 years maybe?
Sure: these are purely schematic and only burdened with carrying a few bits of information (general shape; ultimate level). But yes, I would hesitate to predict the details and non-linearities involved—other than to caution against arbitrary area under the curve.
Don't normal populations increase and decrease with their environment and social situations. Why is there no graph that fluctuates like a sign curve. In a forest with rabbits and foxes the populations never just reach a specific point and stabilize. even if you remove all complicated variables that effect them. With human population the size of the population will effect the culture, the resource distribution, the production, the technological advancement, and many more variables which effect the population. I feel that the population will start decreasing at a certain point then later start increasing again as society changes, but these graphs you have given cover that sort of result. I would say it is a false choice fallacy.
You are correct that nature seldom provides a smooth logistic curve, leveling to stability. Fluctuation is the rule. However, today's human population may be many orders-of-magnitude above what ecology can support: based largely on fossil fuels but also on other non-renewable extractions and one-time environmental expenditures. So, our main feature is likely to be a giant one-time pulse, so that the menu options ask what the future-side of this surge might look like, in broad brush.
Oscillation at a high level (returning to present peak) is essentially ruled out by the "area under the curve" argument: overtaxed ecology and resulting sixth-mass-extinction (also spent resources; will not repeat). Sure: we will likely oscillate around some level, not captured in these crude representations. The question is whether we oscillate around an E scenario or go to F, as oscillating around D seems untenable (whether level or oscillating, little ecological difference). I could have presented many options that look like E but have oscillations around the low level, although I didn't see the point of that, as they would basically say the same thing: dramatic reduction from the modernity peak. I therefore push back on the false choice charge: I don't believe I excluded a qualitative regime, wiggles or not.
I understand modernity will end. Do you think its possible to save some progress? John Gray in is book Straw Doogs Gray scoffs at the notion of progress for 150 pages before conceding that there is something to be said for anaesthetics.
After the oil ends start making ether again?
As you indicate, "progress" is a loaded word, wrapped in mythology. "Something could be said" for every innovation and doohicky, but it is usually beyond our comprehension what the fallout might be. Nature will sort out what is allowed long-term. Whenever I encounter a question like this, I consider other species, in an effort to shake off human supremacy. Do other species need our innovations? To what end do we use anesthetics, and on balance (in the broadest lens), is it a net positive to the living world? While it's easy enough to rattle off some positives to humans, usually, I don't know the full answer. But I think that's healthy, and I wouldn't mind seeing more circumspection on such issues.