a little science-fictional speculation

[eclectic_boy]

Some rather-rambly thoughts on an SF concept I haven't seen before:

I was thinking about how the structure of families and the relationship between parents and children is tied to both our lifespan and to our period of sexual fertility. Humans (and lots of other creatures) are fertile pretty much from the moment they grow into adults, even a bit earlier. Indeed, that's a plausible definition of when a person has become an adult. And they stop being so well before death (on average).

Now, playing around with that may be evolutionarily unbelievable, but given that advances in technology have allowed humans to greatly increase the prevalence of other characteristics that are way unfavorable from a purely evolutionary perspective (as my 20/500 eyesight reminds me constantly) I'm not going to let that stop my speculating. Note that I'm not going to give an explanation for *how* this would come to be -- that can be worked out later if the speculation leads to interesting places.

So for the moment let's just accept that humans still have an 80-year-ish average lifespan, and that fertility starts around age 70. From late teens until then you're adult in every way except sexually. What changes happen to people? To families? To society?



First of all, you can no longer take for granted that you're going to live long enough to have children. If that's important to you, cut out all risky behavior that could kill you before age 70.

Next, parents' lives won't have a lot of overlap with their children's. And nobody will ever know their grandparents/grandchildren. How will families, or society, structure themselves to deal with orphans, which would be common given that many people would be just a few years old when their parents died? Would kinship become less important because you'd encounter less evidence of your place in a generational chain, or would that very rarity make family even more important a part of a person's identity?

How will the start of puberty be viewed by a 70-year-old entering it? By their 65-year-old younger sister? By the society around them? Sure, it'll be seen as a natural stage of everyone's life, but for most people in the surrounding society it'll be something that they've never experienced. Certainly it'll be a confirmation of aging more severe than grey hair or wrinkled skin is to us. Will it be something some people try to hide?

What sorts of structures will people make for themselves during their pre-puberty lives, and how will they deal with the sudden urge to be with a sexual partner?

Of course there are many ways this universe-tweak could play out, many blanks I haven't filled in. For instance, is a 40-year-old in this universe more like a 40-year-old in ours? An 11-year-old with a larger body? A Vulcan sans pon farr? Feel free to tackle some of those blanks, or just tell me what your ideas are about this science-fictional supposition!

Comments

[jere7my.livejournal.com]

Fertility and "the sudden urge to be with a sexual partner" aren't necessarily the same thing. They could be, but children start sexual play well before puberty — it stretches credibility to imagine most people going seventy years without having sexual partners. With the threat of unwanted pregnancy removed, I could envision a world of sixties-style free love, with story complications arising from a virulent new STD or a repressive anti-sex regime.

Society's ostensible foundation for marriage (to provide a stable environment in which to raise children) would collapse. I'm not sure that marriage itself would collapse, though — people might still want partners to share their lives with, as many non-reproducing married couples in our world demonstrate. Without paternity confusion, polyamory/group marriage/open marriage might be more common. There might be a surge of recommitment ceremonies around retirement, as couples and moreples begin to think seriously about having children and structuring their lives to accomodate that.

Population decline would be a serious issue — the societal pressure on septuagenarians to replenish the population would be huge. Boarding schools would be very common from a young age — more like the British system of last century — and would have to be paid for by taxes. (That would sop up the orphans, too.) A lot of young folk would complain about these "draconian taxes", in exactly the same way they complain about Social Security.

I could also see fostering/adoption becoming the norm. If 70-year-olds give birth to babies they're not equipped to care for, they could just be passed on to 20-year-olds to raise, in which case the society looks a lot more like ours.

[sildra.livejournal.com]

Maybe, socially speaking, going through puberty would be something like going through menopause now--some people talk about it, most people don't. Or maybe because it would happen men as well as women, it would be talked about a lot more.

People wouldn't have siblings, at least not in the ways we currently think of it. Extrapolating from modern artificially-induced old-age pregnancies, probably all or nearly all women would die in childbirth, probably on their first child (or, at least, the first child they carry to term, although there would probably also be a lot of cases of infertility-inducing and even fatal miscarriage). Having a child, then, would be a very serious decision, and unless there was a nearly irresistible urge to procreate built in with puberty, I imagine a lot would refuse to undertake it. 70 is somewhat younger than most people seem to be willing to die. If it were 80 or 90 instead... well, assuming everything else about society and psychology were the same (which is a completely ridiculous assumption that I'm just making in this paragraph for simplicity's sake) probably a lot more women would go for it. (Trying to extrapolate further on whether women growing up in this society would be more or less willing to sacrifice their lives at 70 for a child... I could really see it going either way, and society's expectations in this regard would matter a lot. The importance society places on having a child would also determine whether a lot of people would even make it to 70.)

Average life expectancy may be ~80, but that's not the average life expectancy of a 70-year-old, even now (TSOR says life expectancy for a 70-year-old male is about 88). So a lot of children would probably be raised by their healthy-but-slow/tired single fathers.

As for how pre-pubescent adults would act... My 0th order approximation is that it would be something like how single adults act now, especially single adults with single friends. Ambition would be a very different thing, though. Most people make their career choices based on the urgent need to support their families. In a society where people don't have children during their working years, I think most people wouldn't work full time, or would do stints of working and stints of unemployment. Only people who are really self-motivated would work hard. The way to get around this would be to have a society that emphasizes society-before-individual, although I suspect even that would be harder to implement (since that's usually done by extrapolating from family-before-individual).

[metasilk.livejournal.com]

"First of all, you can no longer take for granted that you're going to live long enough to have children. If that's important to you, cut out all risky behavior that could kill you before age 70."

How well is sexual maturity tied with risky behavior? Although I don't think they are independent (now), they aren't 1-to-1 either, I think. Isn't there quite a bit or brain maturation going on as well as sexual maturation? In your scenario, does the brain mature before sexual maturity? Since the desire to have children is driven both by hormonal balances and by cultural ones, will anyone feel the urge to have children (and therefor maybe, pan for and around it) in time to cut out risky behavior anyway?

"Next, parents' lives won't have a lot of overlap with their children's. And nobody will ever know their grandparents/grandchildren. How will families, or society, structure themselves to deal with orphans, which would be common given that many people would be just a few years old when their parents died? Would kinship become less important because you'd encounter less evidence of your place in a generational chain, or would that very rarity make family even more important a part of a person's identity?"

Who would raise the children, then? Would property/inheritance also change? Would children be raised more communally? Would parental kinship be less important, but aunts/uncles/cousins rise in importance? (Came across this, tangentially, today: maybe more food for thought: http://www.tornworld.net/settingpageview.php?id=19#5

"How will the start of puberty be viewed by a 70-year-old entering it? By their 65-year-old younger sister? By the society around them? Sure, it'll be seen as a natural stage of everyone's life, but for most people in the surrounding society it'll be something that they've never experienced. Certainly it'll be a confirmation of aging more severe than grey hair or wrinkled skin is to us. Will it be something some people try to hide?"

Huh. I am reminded of Jane Goodall's TED talk (I think Lane linked to it on Facebook) about the third stage of life. Hm.

Off to read comments then make chicken soup for my little ones.

[eclectic-boy.livejournal.com]

Thanks, Jere7my, you're absolutely right that I shouldn't automatically conflate fertility with sexuality (although I suppose it's possible to set up the situation as one where people just don't have sex organs until puberty).
To what extent do you think the existence of sexual play in prepubescents is driven by exposure to the major role sexuality plays in our culture? If, instead, it was something done only by the oldest ten or twenty percent, and perhaps more clandestinely, might it have little enough prominence in wider society that it wasn't imitated by younger people?

Would young folk complain about the draconian taxes for boarding schools even though such a large percentage of them had themselves been raised in them? I'm trying to work out a consistent way that the almost-all-orphans universe could change family structure to one where children were raised by a larger number of adults - no one adult has the parental degree of closeness to the children, but the hundreds who share some same great-grandparents might all treat them as "kin-enough".

Ooh, there's some interesting time-slice ramifications: People all born in 1900-1910 would have kids born in 1970-2000, with no overlap with people born in the 1940s - not them, their kids, nor their parents. Might there be more of a polarization between families whose phases in the century-cycle were different -- a much more extreme version of, for instance, the blame some lay on the Baby Boomers... because no one in their family would be of that generation? I must muse on that some more.

[eclectic-boy.livejournal.com]

Any version of this universe is going to have to be constructed in a way that doesn't lead to the population completely dying out in a few generations. Technology might be one answer, but I was actually thinking this would be a world where giving birth was easier than it is here, with a much lower mortality rate. So even though a woman is in her seventies or eighties, she's as likely to get through the pregnancy as a 25-year-old is in our world.

Interesting thoughts on lack of ambition. I wonder if a religion could supply that - maybe by emphasizing that only the virtuous will be rewarded with children at the end of their life (the "Sarah Syndrome"?).

[sildra.livejournal.com]

The more I think about it, the more I think the lack of ambition would really screw things up. Being married/having kids is supposed to protect people a lot from suicide, and even the worst sorts of depression, because it gives them something immediate to live for. Insufficient levels responsibility (e.g. unemployment) also contribute to/cause depression, which leads to lack of motivation to acquire more responsibility, so it tends to spiral.

Given how many people, even now, don't bother to do well in school because they don't have the immediate motivation of thinking about their job prospects years in the future when they finish... There might well be a religion in place to supply that sort of motivation. But it would have to be a pretty powerful religion to guide people through that level of delayed gratification--70 years is an almost unimaginably long time for this sort of thing--and not everyone is sufficiently susceptible to religion.

[eclectic-boy.livejournal.com]

1) I was in fact considering the brain to have matured before sexual maturity, at about the same age it does now. Hormones was one of those blanks I mentioned might get filled in in several ways. An hour ago I ran into Scott Gilbert and talked a little about the scenario with him; he was wondering if this meant no testosterone until age 70 and what impact that would have on wars.
Maybe nobody would have the innate urge to have children until 70, but still think it was vital to get to the age where you could have them, It certainly makes logical sense, but logic alone often isn't enough to compel action - so I wonder if some society-level pressure would evolve to keep up the emphasis on living to procreate (such as the religious angle I mentioned above to sildra). And of course I wouldn't neglect the survival instinct. A lot of people are going to want to live for a long time regardless of whether there's a reproductive process waiting for them at the end of their lives.

2) That's the direction my personal speculation is going. See above comment to Jere7my.

3) Thanks, I'm off to track down that TED talk!

[jere7my.livejournal.com]

To what extent do you think the existence of sexual play in prepubescents is driven by exposure to the major role sexuality plays in our culture?

Children engage in sexual activities because it feels good, even before they know about the concept of "having sex." (See the popularity of vibrating toys for toddlers.) Unless you want to postulate major physical changes, I think "it feels good" is plenty of motivation for sexual experimentation, even without the drive to reproduce.

Would young folk complain about the draconian taxes for boarding schools even though such a large percentage of them had themselves been raised in them?

Would rural conservatives complain about government aid programs even though many of them are currently receiving benefits from them? In general, the answer to "Would people complain...?" is "Yes."

[nightengalesknd.livejournal.com]

We'd have something like the inverse of a lot of families I see, where grandparents are doing the childraising. Instead we'd have something like professional childraisers for 18-40 year olds or so for people old enough to be out of school but at something of loose ends. They'd probably get a 6 month childraising class and then start having babies farmed out to them in batches. There would be lots of government involvement, almost to the point that to raise your own child as a 70-year old would be as unusual as having a child taken away and put into foster care now. Not rare as hens teeth, but not the norm either.

On the plus side, there would be less societal looking down on people my age who aren't actively creating children. A young/youngish adult would be freer to be career focused.

[crystalpyramid]

I know this isn't the conversation you're trying to have, but I find it completely unbelievable that, in a situation where humans were able to have children healthily in their 70s, they died in their 80s or 90s. I hear that whole labor and birth thing is hard work, not to mention the actual raising of the children, including through the teenage years. Given how fragile and needy human children actually are, I'd be worried for the future of the species if this were to ever happen naturally.

On the other hand, I can think of more plausible-to-me ways you could end up with people not having kids till their 70s, and without dying in the process. The first thing you'd need is the technological advancement such that bearing children is more detached from one's actual personal body, e.g. artificial wombs or whatever. The second thing you'd need is some reason that people could no longer bear children themselves, whether because of extremely hostile conditions, weird future evolution, or the need to genetically tinker with every kid for whatever reason. Bearing kids artificially would be more expensive, and thus maybe one would need a lifetime's worth of savings and accomplishments before one got to the point where reproduction was feasible. Or I could think of plausible ways that people only bearing children late was due to need to have careers first (as is already sort of happening), or part of some kind of extreme population-control measures.

But anyway. Not the conversation you were trying to have. More on-topic, I think it would seriously mess with family structures. I've been part of a bunch of conversations on the internet, usually inspired by reading the book Promises I Can Keep (which I haven't actually read), and one of the things that comes up in the book is the difference between child-rearing strategies among the rich and the poor. Poor women think rich people who wait to have children are being selfish, because when they're older they won't have the energy to help their children, and their parents and siblings won't be around to help them raise the children, so their children won't get as strong an upbringing. Rich women think poor people who have children early are being selfish, because their financial and educational resources are so slim early in life, while later in life they will have a lot more advantages to give their children. It's somewhat of a rude oversimplification of what I'm sure is a more nuanced argument, but the dichotomy is there. The less time you have with your children, the more you'd better have material things to pass on to them in your absence, because you can't just pour time and energy into helping them yourself.

Such a short period of reproductive years would reduce the age span of sets of siblings, although of course you'd still have crazy families like my aunt who pop out a kid every year or two, so you could still have large families. But it would be harder, I think, because the later the kids are born, the less actual time you'll spend with them. And then why bother? The thing where younger children get less parental attention would be dramatically exacerbated by parents not having to stick around to watch how they've messed up their youngests. If you have your first kid when you hit maturity, your third kid won't be able to read yet when you hit your life expectancy.

[crystalpyramid]

(Hit the comment limit, would put that in the subject line, but LJ deleted subject lines in their last idiotic overhaul.)

Socially, people might be very close to their siblings (having had to endure losing parents early), or they might all drift apart after losing their parents, depending on how things were structured. I'm not sure networks of extended families would really exist -- people would be very bound to their cohorts, age-mates who were having kids at the same time they were, and those peers would become crucially important at that time of life. Having everyone that rigidly in synch for reproductive years would probably mean you wouldn't have a lot of relatives of dramatically different ages — everyone would cycle through more or less together, all your cousins would be about the same age, all your grandkids would be about the same age. Those age-mates would maybe be very close, but the inter-generational family ties would be pretty much gone. Chosen family and friends would probably be much more important than blood family, simply because blood family is so sparse. If you wanted to learn from older role models, you'd have to turn to outsiders.

It sounds even more lonely and materialistic than our current society, without the opportunity to share anything real with families, without the ability to pass anything on except your words and your stuff. And I'm not actually sure there'd be a motivation, other than biological, to having children, if you weren't going to be around to see their lives. Maybe it would be an important status symbol? Maybe I'm underestimating the human need to have a legacy? But what a lot of work for such a small window of togetherness. Human development depends so much on nurture, and if you don't raise your own children, how much will they really have gotten from you? Maybe in a society with institutional or communal child-rearing, where children were generally raised uniformly anyway, and there wasn't so much idiosyncrasy and individualism involved in it, it could be reasonable. Contributing children to the population, rather than having them grow up your own and passing on your values to them. It might be more efficient (more working years, more quality control of child-rearing), but it sounds like it would also be less fun.

[crystalpyramid]

I think we'd die out, unless the people who did have children had huge numbers of them.

[crystalpyramid]

As for how pre-pubescent adults would act... My 0th order approximation is that it would be something like how single adults act now, especially single adults with single friends.

I feel like the prolonged adolescence thing that we have right now, with people our age and older acting like immature teenagers on the internet, would get even worse. A lot of people grow up because they urgently have to; if they didn't have to, I bet fewer people would. (I think this is basically similar to what you're saying, but I want to be sure.)

[eclectic-boy.livejournal.com]

That feels reasonable to me; having kids (or just the knowledge that you soon might -- and that if you wait too long you won't be able to) seems like a strong pressure towards maturity and accepting responsibility. So much so that I actually wonder whether part of why our fertility starts in our teens is *because* it's evolutionarily useful for us to stop goofing off as soon as possible. (Of course, I realize that this would still be secondary to the main evolutionary benefit -- you can have more children if you start giving birth young)

On the other hand, what about the possibility that our extended-childhood is a result of parents and society being there to take care of us, and that if most people lost their parents at age 10 there wouldn't be such a strong source of care? It seems to me that a common phrase I hear about people whose parents died when they were young is, "[she/he] was forced to grow up at an early age."

[sildra.livejournal.com]

It's similar to what I'm saying. My experience from looking at my single friends (ranging from my age to a generation older) is people mostly stop liking certain sorts of teenager-ish stuff (partying, etc.) starting somewhere in the mid-20's to late-30's range, although certain types of people keep it up even longer. But anyway, there are certain sorts of behaviors that young, unattached adults engage in that I don't think most 50-year-olds would. I do think people would retain a childish selfishness a lot longer, but I also think a lot of people with kids don't necessarily give that up, either. So... I'm speculating that people would act like teenagers for maybe an extra 10-15 years, and people would generally be more selfish but maybe not to a point where that alone would make society unrecognizable. So, basically, yes, like our prolonged adolescence, but still probably not prolonged all the way out until 70.

[crystalpyramid]

Humans are such a k-selected species, high parental investment, low number of offspring, that decreasing the level of parental investment seems really dangerous to me, unless, I suppose, you had everyone have more children.

Maybe you could have a reasonable sort of society with strong "godfamily" relationships. When you are in your thirties and forties, you help rear other people's children, because someone has to. When your children are born, you appoint the children you raise to be the godparents of your own children, to help raise them after you are gone. You know that they're good people, because you did contribute to raising them, and there's a meaningful tie there. These people, in turn, appoint your children as the godparents of their own children. Thus you can have family continuity and culture being passed on, even though you miss out on most of your own children's lives. And you can still have strong family ties, but in a symbiotic kind of relationship between two mostly unrelated (or distantly related) families that are half a generation out of synch.

Maybe it would be advantageous for children to have different people dealing with them as teenagers than raised them as infants, because the second shift of parents wouldn't have so much trouble adapting to the idea that the children whose lives they once had to control completely, were turning into thinking people. I can't see a lot of other advantages, though — if society was structured as above, it would basically mimick our current society, just with farther-delayed gratification.

[sildra.livejournal.com]

I'm tempted to say that even if the people who do have children have large numbers of them, we'd still die out.

I can't find any way to look at this that isn't a clear dystopia where large swathes of people are miserable. Every time I come back to thinking about this I think of new problems. (New problem: in addition to depression/suicide, boredom and lack of responsibility would lead to all sorts of society-wide drug problems.)

[q10.livejournal.com]

probably all or nearly all women would die in childbirth, probably on their first child (or, at least, the first child they carry to term, although there would probably also be a lot of cases of infertility-inducing and even fatal miscarriage)

this is not a recipe for a self-sustaining population. i think we need to tweak the assumptions in some way to exclude this case.

[q10.livejournal.com]

i think you're keeping too much of the basic human programming constant. humans are lost without children because their evolutionary programming is incentivizing them to procreate during their peak child-bearing years, not because it's some unshakable law of the universe that any human-like intelligent organism must be lost without children.

[sildra.livejournal.com]

Are we supposed to be assuming non-humans, then? I thought we were assuming humans, but where everyone takes puberty-delaying drugs until they're 70. (Plus Jim's reply to me above where pregnancy/childbirth isn't nearly as physically taxing.)

[q10.livejournal.com]

i think to make this work we have to envision that children, when born, are very different creatures from human infants as we know them. first, it needs to be easier and safer to pop them out, for reasons others have mentioned. there are a lot of options here (the marsupial solution springs to mind, but there are other options). second, children need to have a much shorter period of parental dependency - probably no more than five years. that doesn't mean they need to be self-sufficient persons in five years, but they need to be at least self-sufficient animals in five years. or else there needs to be some incentive for unrelated adults to care for them. i think we just make them self-sufficient animals that mature into intelligent persons on their own. we assume that they eventually get taken in by social groups because social groups benefit from cooperation.

the natural point of departure here, in terms of real animals, is cephalopods. they can allegedly be pretty smart, by invertebrate standards, but most have a spawn-and-die type of life cycle. what you're proposing is basically a stretching out of that idea across a longer span of time.

[q10.livejournal.com]

i feel like we need permission to make enough changes to the other aspects of these people's hardware and software to bring the world back to some kind of coherence. i agree that, without such freedom, this is prettymuch a non-starter.

[sildra.livejournal.com]

But if we start changing stuff too much we might as well start from scratch. And then we can make up whatever we want and it becomes an entirely different (and in my opinion, less interesting) exercise.

[glassonion]

I think "most people are raised by their biological parents" is not a helpful norm in this situation, since you'd have well over 10% of the population orphaned before kindergarten age, i.e. at an age where it's really not physically possible for them to take care of themselves. Unless this is a "scores of children dying on the streets" type dystopia, i think you have to wind up in a situation where the large number of healthy adults without their own kids, are brought in to do child-rearing.

Given that, the question of whether there's any chance that you wind up with adoption into two-parent families is a reasonable one. I think it's pretty unlikely --- the notion two parents would just not be that privileged if it hadn't been necessary and sufficient to produce children at all the points when norms were being developed.

So maybe you wind up with much more of the kibbutz type model (as i very imperfectly understand it), in which a bunch of adults do a variety of productive things including raising the kids en masse, and a visit from a biological parent is a special treat. That's what i got, anyway.

[rose_garden.livejournal.com]

This makes sense to me.

The one thing no one seems to be talking about is that we live much longer than our ancestors did. In the hypothetical late-fertility scenario, I can't really picture the history of such people.

[sildra.livejournal.com]

The one thing no one seems to be talking about is that we live much longer than our ancestors did.

Yes and no. Our ancestors tended to die much younger than we do, but we don't live that much longer than them (maybe a decade or two). I had a great-great grandmother who lived into her mid-90s, for example. When people talk about how our society has a much longer life expectancy most of it comes from huge strides in preventing and curing childhood diseases. TSOR indicates that in ancient Rome, for example, at birth life expectancy was 25, but if you survived to 5 years old it was 48, and if you made it past your teens you were likely to live at least into your 50s. If you survived to 60 you'd probably live to see 70, etc.. They do find 10,000-year-old skeletons of people in their 70s and 80s when they excavate neolithic graves.

As for picturing the history, my interpretation of the prompt is basically take the world as it is (or I was simplifying to just first-world societies), change it right now so that people start procreating at 70, skip over the transition period and try to describe what steady-state (if any) the system will reach.

[eclectic-boy.livejournal.com]

Indeed you may! It'd be interesting to see what different variations people could posit would allow this scenario to exist, especially how it could be achieved with as little change as possible.
Naturally, if we all agree that my initially-stated situation would lead to humanity having long ago gone extinct, that's suboptimal. And boring.

I have to say, the ethnographic part of me is fascinated to consider why people in that world might conclude that *our* biology would doom *us* to a dystopia. (Remember Arthur C. Clarke's short story "Report on Planet Three", in which Martians conclude based on their analysis of Earth's conditions that it would be too harsh to support life?)

[crystalpyramid]

Are there tweaks you're envisioning to human children that would make them self-sufficient animals by age five? I feel like messing too much with the capabilities of children would entail making them sufficiently non-human that it stops feeling relevant, but maybe I'm missing something.

The main self-sufficiency children don't have right now is procurement of quality food, right? And that could be solved environmentally, I suppose, by making food more readily available. (Subsidies and stipends on the socialist side, or an extremely hospitable planetary environment on the fend-for-yourself side.) Would that be enough? What else can't kids do?

I think children are probably actually much more capable than modern first-world society gives them credit for.

[crystalpyramid]

Problems with our system that they might see:

• How would you ever get anything done, if you had to spend all your most productive years raising children? No wonder the original humans took so long to achieve spaceflight!
• Gender inequality. The idea that women and men are economically unequal, women's wages are lower, women have more difficulty getting promotions, etc, would be completely alien to them, because most of that stuff stems from women historically having to spend their energetic years bearing and caring for children. They might be a lot less uptight about same-sex relations, and as carpenter suggests, the one-man one-woman partnership model would be a lot less fundamental. Children would probably be raised in a much more gender-neutral way.
• Romance would be alien. All those aspects of first love where it's precious because it's the first time anybody understood you, or tried to. All the beauty of naivete that comes mixed in with the idea of love, along with all the mistakes people make in relationships because they just haven't figured out how to understand people yet, they would all seem stupid and pointless to people who didn't procreate till they were older. Children with unpleasantly divorced parents would probably be a lot less common. Older people, even under the influence of new hormones, would probably be a lot more pragmatic, simply due to the weight of experience.

[crystalpyramid]

If you tweak the age of fertility by a few years, so that most children lost their parents at age 15, I might buy your argument that it would be an incentive for people to grow up and fend for themselves. However, a lot of the struggle of losing one's parents at 10 is learning to cope in a society designed for people to lose their parents at 50. If everyobody lost their parents at 10 (or 15), more social supports would be present, and it wouldn't be nearly as much of a shock/struggle.

[sildra.livejournal.com]

I kind of like (as an interesting story, not as an actual society to live in) my version where death during childbirth is the norm and surviving to have a second child is the exception. I'm imagining this would result in extreme gender inequality: women aren't allowed to do any difficult manual work because they have to still be healthy enough to carry a child at 70, they get pampered and protected a lot possibly to the point of being infantilized, basically there's a whole cult around women and it just gets worse the older a woman gets. Kind of a queen bee/ant thing, except that all the women are potential queen bees and you need all of them to survive.

[q10.livejournal.com]

yeah, i don't know how far off from self-sufficiency five-year-old humans really are. the tweaks on that end might be relatively minor.

the main thing i want to change, really, is brain size at birth. i mean, that's what makes them so unwieldy to begin with. i want them to come out with smaller brains (and so smaller skulls), and i want their pre- and post-birth development to emphasize a fair amount of anatomical self-sufficiency, and good hunting/foraging instincts, over the development of huge brains and the full package of higher cognitive capacities, some of which may develop early, but which can in a pinch be put off.

one idea might be that after being turned out by their parents after a short dependency of a few years, children are capable of forming up into bands/packs with other comparable age children and hunting and foraging like stray dogs while they gradually finish developing into something with more of the full human cognitive package.

[q10.livejournal.com]

maybe fertility is something activated by some system of pheromone triggers, so that you mature sexually if you spend a prolonged period of time without coming into contact with anybody older than you. this would mean that, as life expectancy increased, target fertility age would too. it would also meant that young people accidentally stranded in isolated places would hit this point much earlier in life, leading to a lot of awkwardness if somebody later found them and tried to integrate them back into society.

[eclectic-boy.livejournal.com]

Except unless you tweak biology so that triplets-and-above are common, the population is going to decline with each generation - perhaps steeply. I guess another tweak that would permit a replenishment-level birthrate would be to have almost all people be female. It's those nonduplicating males who really cause the population shrinkage if the average woman gives birth to, say, 1.2 children.

[eclectic-boy.livejournal.com]

I think that's an awesome take on the concept, thanks!

[sildra.livejournal.com]

Yeah, I'd been thinking about that. As it is now, more males are born but they have a shorter life expectancy. Under this new system there'd be a lot of selection pressure for girls to be more common. Of course, if nearly everyone is female, you don't get the cult thing I described above.

The answer seems to be that you need to tweak the biology beyond just changing reproductive age, but once you're doing that there should be a lot of possible solutions. Since your questions were originally about society, I think we'd have to pick a specific biological solution and then try to extrapolate a society from that. The more we tweak the biology, the easier it is to imagine this working, but the harder it is to extrapolate the society. (And, I think, the less human our projections become, the less interesting of an exercise it is--it starts to become world building for the sake of world building, detached from anything recognizable, and I, at least, only find that interesting in the context of a real story with a compelling plot and characters.)

[crystalpyramid]

That's a cool idea, and it eliminates one of the major reasons everyone is going to die off within two generations. Adds robustness (although I still think any kind of late-breeding society is going to be less robust, biologically). Awesome.

[crystalpyramid]

Hmm. Are there in fact any mammals that have dramatic brain growth later in life, or is this basically a thing that none of our relatives can currently do? It's certainly true that babies' giant brains are one of the big constraints involved in our current setup. Is it harder to develop brains later, for some reason?

I find the idea of bands of six-year-olds with deliberately decreased cognitive capabilities foraging like stray dogs kind of terrifying, but it does definitely create a weird science-fiction feeling world...

[q10.livejournal.com]

i imagine it must be pretty standrad for marsupials, which climb out of the uterus looking like itty bitty fetuses with giant claws (the claws are for climbing up the mother's fur into the pouch, where they continue their development).

i think that, besides that, the closest point of comparison here is humans, who, i believe, undergo proportionally more brain development post-birth than other placental mammals.

but, yeah, this is a serious deviation from normal mammalian design parameters.

[q10.livejournal.com]

although we mainly aren't supposed to be interested in the history, i think imagining an early-stage version maybe instructive for coming up with something plausible.

imagine that the triggers are more complex, so that one or two super-old people don't prevent the onset of fertility, but that you have to be at the old end of your population, on some kind of percentile basis (and maybe have to be over some minimum age).

so paleolithic hunter-gatherers in this species will live in, say, smallish extended family bands, with the onset of sexual maturity between the ages of thirty and forty. older women will spend prettymuch all their time incubating and bearing children, and older men will be almost entirely concerned with infant care. infants will be born smaller and with less developed brains, and will do more developing ex utero. this will both make pregnancy less risky and shorten the gestation period, making it more plausible for the older women to have enough offspring to perpetuate the species. if we can tweak the biology this far, the older men should be the ones who lactate, as this will reduce the nutrient and energy burden on the mothers. (if we're allowed to have a population of marsupial people, the older men are the ones who have pouches to carry the infants through the later stages of development.)

once children are old enough to be put to work foraging for grubs and pounding roots and so on, they're turned over to the slightly older children and early adolescents who run the foraging bands. the younger adults (say ages 16-30) are concerned with hunting, with most leadership roles, and with big-picture child-management stuff.

this all seems like a basically stable arrangement, as far as these things go. but the development of social support institutions as the life expectancy and amount of social structure increases will look very different from what we're used to. note that, for example, any mode of living like an army barracks or a college dorm will probably have biological consequences that are deemed socially unacceptable. in generally, there will be a lot of opportunities to structure the society to engineer the point at which people reach sexual maturity. the details of all this will depend on how we tweak the triggering conditions, of course.

[crystalpyramid]

Giving the men pouches would definitely help with the gender equity thing I was talking about!

Also, your scenario where college dorms might lead to premature sexual maturity, would make it easier for strange new religious/social movements to recruit groups to their cause, and not let them escape again. You recruit a bunch of twenty-somethings to your cult, they all hit maturity and reproduce, and none of them can ever really go home again...

[crystalpyramid]

Lydia suggests that the pheromone thing might sabotage the whole old-people-reproducing thing entirely, though. Instead you might have a society where, at a certain point in your life, you and your chosen partner go off and isolate yourselves until you can reproduce, and then come back after that rite of passage. Possibly this would result in strong pair-bonding, unless you had flocks of young people all going off to do the rite of passage together, in which case it wouldn't. Like college, only longer, and with more babies and fewer professors. This would depend on culture.

[q10.livejournal.com]

okay, so what if the triggering age range has a relatively high low end, like 25 or 30 years, and only activates in response to a certain quorum population (~10), and it takes a couple years to kick in? or some combination of those, anyway? this will make the couple quest impossible, and the flock orgy quest involved enough that it's limited to cults.

ooh! or maybe the onset of sexual maturity is one of the things that triggers a lot of the things we think of as age-associated decay - like people are built to use themselves up spawning. so whenever you activate, you're not good for much more than ten years.

[metasilk.livejournal.com]

Pretty sure human brain reaches maturity in 20s according to current research? Maybe I am misreadiung/misremembering...