The demographic future

[rebeccmeister]

The most recent issue of the journal Science has an "expert voices" article on The demographic future that we do not know about. It is paywalled, but if population demography is a topic that interests you it may be worth figuring out a method to access it.

The main thesis of the article deals with how a narrative about "the demographic transition" has been the major narrative about population demographics for much of the 20th century, but about how now, that narrative isn't so relevant anymore (we're largely past the point of a demographic transition on a global scale) and new thinking is needed about what could happen to human populations in the future.

If you aren't acquainted with it, the "demographic transition" refers to a change in population-level demographics that seems to occur whenever human populations get better access to education and other aspects of modern life (healthcare, etc): there tends to be a shift from high mortality and high fertility, to low mortality and low fertility. That has indeed played out across many human populations across the globe; so the question now is, now what? What will happen next?

The article notes there's a general consensus that the human population will likely peak in the second half of this century, and then decline. People quibble over the details, but not over the idea that human population growth will become limited.

This is kind of a big deal. Historically, there have been hysterics over the consequences of exponential human population growth. And think for a moment about the era of China's one-child policy.

But what will happen under an alternate scenario, and how will it happen? We're seeing some extent of population contraction in the northeastern U.S. right now, and it's hard to know what to make of it all.

Comments

[ranunculus]

I personally think that humans have WAY overpopulated the world at this time and a general contraction would be excellent. In terms of economics there will be a rough patch because the general economic model is for ever expanding trade, something that is ultimately completely unsustainable. It means that culture will need to change its values, again not an easy thing. The good thing is that there are a lot of people out there even now that are doing their best to model cultural change. As far as I can see, you are one of them.

Thoughts

[ysabetwordsmith]

>>The article notes there's a general consensus that the human population will likely peak in the second half of this century, and then decline. People quibble over the details, but not over the idea that human population growth will become limited.<<

Generally speaking, a population of any species will increase to near carrying capacity, then reduce as limits kick in. Some are environmental, others contextual. So for instance, the more crowded the conditions, the lower fertility tends to get -- with a few odd exceptions like locusts that have a swarm mode. While human population would drop, after a time it would get low enough to activate higher fertility again.

However, that's looking at population largely in isolation. It doesn't account for things like climate change, environmental foreclosure, famine, war, etc. Those factors will almost certainly knock down human population a lot faster.

>>But what will happen under an alternate scenario, and how will it happen?<<

Well, we already have one example in progress. China's 4-2-1 problem will cripple its ability to do anything on a global scale in the fairly soon future as it struggles just to survive.

However, there are other possibilities. People might band together in groups to raise a smaller number of children together. They might switch to economies that don't rely on constant growth.

Less human mass is a good thing for Earth, since the current 8+ billion homs are wearing out the planet.

Re: Thoughts

[rebeccmeister]

It's important to understand, however, that the reasons why populations go through cycles can vary tremendously, depending on the organism at hand. It would be far better for humans to not experience population crashes for the same reason other organisms do, running out of resources/food. And while some human population growth is tied to an expansion of access to resources, the demographic shift is distinctly, qualitatively different.

The fallout from China's one-child policy is definitely going to be an extreme case!

And yes, it is absolutely the case that less human mass (and, ideally, correspondingly less human livestock mass) would be much better not just for the planet, but for humanity in general! The challenge is whether it's possible to find a balance in it all.

Re: Thoughts

[ysabetwordsmith]

>> It's important to understand, however, that the reasons why populations go through cycles can vary tremendously, depending on the organism at hand. <<

That's true, but the carrying capacity is a hard limit for all species. Each needs a certain amount of air, water, food, etc. per member. The limiting factor may vary, other variables may play in, but there's always a limit of how many will fit in a given space.

>>It would be far better for humans to not experience population crashes for the same reason other organisms do, running out of resources/food. And while some human population growth is tied to an expansion of access to resources, the demographic shift is distinctly, qualitatively different.<<

It would be better, but humans are prone to fighting over things when crowded, and hell, making up reasons to fight even before then.

>>The fallout from China's one-child policy is definitely going to be an extreme case!<<

I really have no sympathy. It only took me a few seconds to pinpoint several major flaws in that plan, and I was pretty young at the time.

>> And yes, it is absolutely the case that less human mass (and, ideally, correspondingly less human livestock mass) would be much better not just for the planet, but for humanity in general! <<

Sooth.

>>The challenge is whether it's possible to find a balance in it all.<<

Sure it is. Plenty of societies did that in the past. Some still have those premises. The problem is that they've been overrun by expansionist societies with less ethics and common sense. I mean "Don't saw off the branch we're all standing on" is not rocket science.

[mallorys_camera]

I've been speculating about the demographic transition from my own little niche of healthcare economics. Like right now, medical capacity is being over-built enormously to deal with the death march of the Boomers, right? 😀 But what's going to happen to all that excess capacity in 30 years when the last of the Boomers is dead? They're gonna have to try & keep monetizing it somehow. I suspect they'll do that by fetishizing preventive medicine: Everybody needs a yearly CAT scan! Something like that.

[mellowtigger]

Demographic changes are behind my employer eliminating some of its campuses in Pennsylvania. These pages describe the shift in number of people, the urban-vs-rural location of those people, and funding/affordability problems.

edit: When you spend decades preventing wage increases for the poorest while excusing taxes for the richest, then eventually many systems become economically unsustainable.

https://www.psu.edu/news/story/update-factors-informing-commonwealth-campuses-recommendation

https://www.psucollegian.com/news/administration/the-numbers-behind-penn-state-s-campus-closures/article_642e7fb2-8932-47a1-b58b-3e6b8f69d893.html

https://apnews.com/article/penn-state-university-campus-enrollment-710a6362a0a67c16bb30d90a66ed561d

[altamira16]

So I am on this school accountability committee that sucks because parents in the town I live in are nuts, and I put in a slide on demographic data from the state demographers' site. Our county is going to lose enough children to fill our two biggest high schools in the next ten years, so I want teachers and parents to understand this is coming and quit fighting over stupid nonsense.

[rebeccmeister]

It sucks that human beings are so bad at these kinds of things! (focusing on the difficult problems that need attention instead of squabbling over stupid stuff).

I think it's especially hard to work with parents. A lot of them are involved from a self-interested perspective, and that means they want things a certain way NOW, to hell with the future. Ugh.

[twoeleven]

But what will happen under an alternate scenario, and how will it happen?

In the short term, we do have the Japanese example to study: a shrinking population is an aging population, and to provide the goods and services they want, an increasingly urban one. This was already happening anyway in the US, for a bunch of reasons (abandonment of marginal farmland, young people looking for jobs in cities, both of which lead to a vicious cycle of collapse of rural services).

Japan's experiments with personal robots also look interesting: sooner than we run out of people, we'll run of out people willing to care for the elderly, for example.

The same goes for agricultural automation, but there the consequences are more varied. An article read a while ago pointed out that right now, hand-picking fruits and vegetables means that large crews pick everything that looks roughly ripe at once (maybe twice for a given field/orchard) and it's all shipped at once. But machines can, in priciple, pick only what's ripe or about to ripen, and visit a field repeatedly, which means a continuous supply of ideally ripe fruits and veggies, and potentially less concern for shelf life.

[rebeccmeister]

It's kind of interesting to think about whether (or not) different places will react similarly as demographics continue to change more broadly, although I do agree it's useful to look at the Japanese as one example. I just don't think there will be any sort of uniform equivalent of the "demographic transition" for what happens on the other side of population restructuring. And yeah, you've got a point, regarding urbanization, although urbanized areas still rely on at least *some* people continuing to live in more rural spaces!

I'm wondering if some of what happened in nursing homes during the early stages of the Covid pandemic will be foreshadowing for what will happen more generally as populations age and there are even fewer able-bodied people willing and able to do full-time eldercare work. Not a pleasant thought, but kind of an important one, there!

Whew, automation of fruit and vegetable harvesting still sounds like an exceptionally daunting project, even setting aside the selection of items based on ripeness (if it wasn't, we'd already be doing it?). Plus it all depends on continued advanced manufacturing methods, having people who can repair the robots, and having farming economic systems that make that sort of mass growing and mass harvest feasible.

So, I remain skeptical about the future under our robot overlords.

[twoeleven]

It's kind of interesting to think about whether (or not) different places will react similarly as demographics continue to change more broadly, although I do agree it's useful to look at the Japanese as one example.

I think the economic drivers will tend to dominate the discussion, which will lead nearly all the industrialized countries to the same narrow set of solutions, with the possible exception of France and other countries that subsidize rural people. Though to be honest, why would a bunch of young urban people continue to subsidize a lifestyle that doesn't mean anything to them?

I just don't think there will be any sort of uniform equivalent of the "demographic transition" for what happens on the other side of population restructuring.
I guess we'll find out. :)

The peak of the US baby boom ended in 1959, and those people are now 66, and just starting to retire. In a few years, they'll hit median life expectancy at birth for people their age, and start dying in droves. And that's the end of the baby boom, so all the older Boomers will already be dying off by then. So, that should mark the start of The Change.

urbanized areas still rely on at least *some* people continuing to live in more rural spaces!

Sure, though it's a few percent of the population.

I'm wondering if some of what happened in nursing homes during the early stages of the Covid pandemic will be foreshadowing for what will happen more generally as populations age and there are even fewer able-bodied people willing and able to do full-time eldercare work. Not a pleasant thought, but kind of an important one, there!

Horrific conditions and scandals are already too common. Both here and in the UK, there have been serious enough cases of neglect for politicians to change the laws. But I suspect that rising labor prices and/or a simple lack of interest in people wanting to care for people in nursing homes may just shift the problem to old people dying alone at home.

Whew, automation of fruit and vegetable harvesting still sounds like an exceptionally daunting project

It is; the technology is barely out of the lab. But agricultural automation is already here: modern tractors and combines can drive themselves perfectly well. Farmers, agronomists, and environmentalists are already looking forward to robots that can repeatedly cross farm fields to catch the earliest signs of weed, disease, and insect outbreaks, allowing them to be stopped with as little use of *-icides as possible.

if it wasn't, we'd already be doing it?

Partially yes, partially no. The development of rechargeable lithium batteries has really changed the game for robots. Electric motors are tiny compared to internal combustion engines of the same power output. So, now it's possible to send small machines out into farm fields, just with the caveat that they have to recharge relatively frequently.

farming economic systems that make that sort of mass growing and mass harvest feasible.

Anybody farming fruits and veggies for their income will have enough plants that they need to hire people to help bring in the harvest. For the staple crops, harvesting has been mechanized for around a century, and that was one of the big drivers for urbanization: there ceased to be a need for large numbers of people to harvest crops.

Fruits and veggies typically sell for a few dollars a pound, right? The median household income these days is around $70k, so that's around 30 tons of fruits and veggies to harvest. Even with a long harvest season, that's a lot of work. Feel free to adjust the numbers to taste or run in real data. :)