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Almost Hilarious Poplulation Growth
So In the story I've been working on, there is a five billion strong nation that nobody noticed because they were hiding under Antartica. Now, currently, in the story, the current explanation is that this was an initialy a few families of about a thousand people that balloned into that number in about eighty years.
Now, my question is, can you call BS on this? The society here is primarily dedicated to increasing the population by any means neccessary (for example, it's law there that women capible of pregnancy, must be pregnant as much as possible)... so just assume maximum human fertility being used almost industrialy. Is this possible or do I get to go back to the drawing board?




Five BILLION in 80 years? BILLION? You realize that there are only 7 billion people on the entire planet, right? I don't think it's humanly possible for all of them to even fit there, let alone have the resources to support that kind of population. How do they produce food for that many people? Fish in that area would go extinct almost immediately if you were trying to feed 5 billion people with only the resources in a close enough range that other people wouldn't even know they existed. Where do they get building supplies for shelters? Furs for clothing? Again, animals extinct immediately. There's no way to grow stuff there, or people would live there already...
5 million I could mayyyybe buy. 5 billion I can't. At all.
For all that the math is done in this thread, I as a reader wouldn't even get that far. I'd see "Five billion", and I'd instantly think to myself "this author has no idea how large a number that is". Because I see this a fair amount, where a big number's thrown out that's instantly implausible. Unless the author themselves breaks down how it actually happened (and in many cases that'll just distract from the story) it's a bit of a suspension-of-disbelief-breaker.
Yeah, absolutely. I tried to see what was possible, because it's fun exploring those things, but unless there's immediate explanation of a number that high (even in the millions), I'm probably checking out because it's just too ridiculous for me. And with billions I'm probably not even going to buy whatever the explanation is because just the sheer amount of space to hold them is impossible as well.
And as you said, you want a story that can flow naturally and you don't have to stop and explain every single thing, or that's going to make for not as good of a story in other ways.
If you want to go from 1000 to 5 billion, some quick calculations show me that you could possibly do that if 100% of them were female, they only had female children, and 25% of the entire population (including the babies) had at least one baby every year.
So no men, only a sperm bank and artificial insemination, maybe? Can't imagine why anyone would bother.
But to answer your question, 1000% BS, would not believe. Not because of population stats (though those are ridiculous and hilariously so), but because attempting to live inside an ice sheet is about as plausible as a journey to the center of the earth.
Antarctic ice sheets are neither stable nor solid, and attempting to build permanent structures large enough to host 5 billion people will end with those structures being a red layer of jelly that's, maybe a few centimeters thick. I mean, if they're higher up, then they're in the fracture zone, and whatever structures they make will be cracking like a KitKat bar. Lower down...nah. Not even possible. The ice sheet would collapse in on them, or flood, or do any one of the millions of incredibly inhospitable things that glaciers and ice sheets do. The immense pressure and weight of the ice sheet means that ice tunnels are extremely prone to collapse (even in baby glaciers like you find on mountains, they tell you not to go into those ice tunnels for a very, very good reason), and as ice sheets move, they tend to crack and shift and collapse in on themselves--hazard of a very brittle solid moving like a liquid under the pressure of its own weight.
You have to keep in mind that ice is a delicate material with extremely crappy sheer strength, and the Antarctic ice sheets are so massive that they depress the actual crust of the earth. Basically, any kind of dwelling would be a weak point in the ice, and would likely sheer and flood with ice water, just flood with melt water, or collapse in on itself (the last is the most likely, I'd say, but it's been a while since I reviewed glacial dynamics, I could be wrong.)
Yeah I think this might be that one plot hole in the story everyone's supposed to ignore, sort of like how there were no winds on mars strong enough to push over the ship in the Martian. There are some borderline miracle technology already in the story that I could explain away that problem with... but anyone who has reviewed glacial dynamics will be right to call BS.
Hey, it's your story, but, like, it's not just glacial dynamics that tell you it's pretty impossible. Pretty much any engineer, geologist, geographer, statistician, history buff, medical professional, or woman has got to take one look at the location or population numbers and go WTAF? Bodies, people, population growth, and ice just don't work like that.
You want to make it work then you can lengthen the time scale, lower the final population, raise the starting population, figure out where they're getting any kind of materials but water, and work at the surface of the ice sheet using fiber of some sort (sawdust, paper, hemp, fabric) frozen into extremely low-lying ice structures somewhere really inland. And figure out food, clothing, and heat for a couple million people at a minimum. Antarctica is quite inhospitable.
Edit: Sorry, forgot to clarify. Adding fiber to ice both reduces its melt rate and significantly increases its sheer strength. You still can't do it inside the ice sheet but dome-like structures dug into the ice sheet (the surface layer of which is usually packed decade-old snow, not ice) might work.
Yeah... I guess it does sound stupid, but there is a few things I forgot to mention because I have been working on this for a while and just assumed everyone knew.
First, this is literally under the ice of Antarctica, as in they carved it themselves, which, as anyone who sat in an igloo can tell you, is a stupidly good insulator. Second, they have fusion technology... which means they have more than enough power to grow crops hydroponicly to feed themselves and the livestock I frogot to mention they brought. Also, they would be close to bedrock, which means they have a stupid amount of stones and metal to build stuff. Also the reason why they're trying to expand their population this much is because they want an army for WORLD DOMINATION... so genetic defects from stretching the gene pool that hard won't matter when most of them die trying to conqure the world.
Just assume that throught those things... they find a way to keep a population that big alive enough. The actual question I want to know would it be possible for this kind of population growth to happen ASSUMING IDEAL CONDITIONS.
I'd use population growth calculators then and just figure out how many healthy, fertile females you start with, plug in the amount of kids they'll probably have (I'm guessing 12-24 when it comes to maximizing pregnancies), then you have to at some point figure in the higher mortality rate due to inbreeding/defects, and grab your number.
There are population growth calculators online, though I can't seem to find the one I used before just now.
Ok, so here's my best attempt at math, given that I'm definitely not a math person. You said "a few families of about a thousand people," to start with. I assume you mean that the families add up to a thousand people, because I don't really think of a group of 1,000 people being a family that you would have a few of.
So let's say you have 1,000 people. For ease, we're going to say exactly half, 500 people, are women. Also for ease, we're going to say that the population is perfectly distributed between the ages of 0 and 70. Of those, assuming that you're starting girls are eligible to bear children from 15-40 (since you said capable at all by any means necessary, I'm assuming they're starting young), that means about 35% of them are within child-bearing range, so 175. Not every woman is going to get pregnant every year, since being pregnant does take a long time, usually your body naturally makes it more difficult to get pregnant while you're breastfeeding, some people just aren't as fertile, etc etc. So I would say, super optimistically, that maybe 2/3 of those women get pregnant each year. So for the first 15 years, you add 117 kids to your population.
For the first 15 years though, your child-bearing population is going to stay approximately the same as women age in and out of that range, at about 175, and about 117 giving birth each year.
After 15 years, you now have a total population of 2633 people. Of those, you have 83 new childbearers, 2/3 of which will get pregnant/give birth that year, so 55. Now your total is 221 kids born each year. Each year after this, you'll have 83 new people going into the baby-making system and 14 people aging out.
Now you start exponentially increasing your population size, but this still only puts you around 8,000 people by year 30.
I'm a horrible math person, so I didn't bother to try to figure out how many people would age out every year and just kept it at 14 forever, even though that wouldn't be accurate after a while. And because I think I probably did something wrong and it should have been exponentially growing from the beginning but I don't know how to think about those things, I extended the pattern out to 100 years instead of 80, thinking that that might be closer to what it should actually be.
So, assuming ideal conditions, that inbreeding doesn't become an issue over 80 years when starting with 1,000 people, and crappy math that errs heavily on the side of giving them as much possibility for population growth as possible, that still gives you only 485,000 people.
This also assumes, again, that women are in childbearing range for 25 years AND that they give birth 2/3 of those years, which is 16.7 kids per woman, which is pretty crazy town, so it would honestly probably be much lower than that. Plus there's gotta be some kinda sickness or something at some point. So... even with acknowledging my horrible math, I just don't see how it's remotely possible.
Screenshot of spreadsheet math here for reference
Also, this was not what I should have spent an hour of my day doing. Oh well!
That is pretty impressive... thought I meant a few thousand... about ten thousand, maybe a bit more, maybe a bit less. I might expand on your basic math to see if I need to revise the numbers.
Ah okay, I just saw that you said "about a thousand people." If you start with 10x that, then you could get to 4,850,000 people, so that's much more reasonable to have millions of people.
Wow... then the numbers for this absurd plan actually check out...
Yeah, kind of. There are still some major caveats to getting to this number and my math is super shitty, but you can manipulate things in some of the ways other people mentioned—if you assume that through medicine/technology women really can be constantly pregnant, that you could manipulate them into having multiple children per pregnancy every time, if you were also able to manipulate to having more daughters than sons so they could reproduce even faster, etc. Probably still keeps you in single-digit millions no matter what though, and definitely not billions.
But what if I also made the starting population ONLY couples in their early 20's consistently going at it like wild badgers, plus science to make twins more likely, and artificial insemination to force pregnancy consistently.... that might make it even more exponential. It would mean you start with anywhere from 5000 to 10000 couples breeding at the start, and in fifteen years, assuming an ideal-ish population spread... they will have their offspring join in... and fifteen years after that... the exponential growth would start getting silly.
Okay, so if you start with 12,000 women and 3,000 men (assuming that you're not bothering with monogamy if you're going for maximum population growth), all age 20, and you've managed to guarantee that on average everyone woman has 1 child every year, whether that's because you can guarantee pregnancy or because some people have multiple babies while others get a break, and if you assume women are able to have children from 15 to 40, then that actually makes all the math a lot easier and you would end up with 17,997,000 people at year 80 and hit 142,065,000 at year 100.
or just 12000 men and 12000 women?
But either way.... this actually makes sense... I just have to make sure they mention the initial number about 20,000... and someone on the future internet gets to do this entire process again... assuming it is the crazy novel this is a part of actually gets published
Why not just go with in vitro, instead of physical pregnancy? If they have the tech you say, growing babies in a lab should be no barrier and it would be far more efficient. All you need for the colony then is your scientists and support staff. So say there is an even 50/50 mix of the sexes, at several labs across the settlement, growing the soldier babies and raising thier own children to continue thier work of growing and developing thier takeover army. Doesn't that make more sense than a strictly low/no tech bodily based breeding program? Particularly if you can make certain that every single fertilised embryo develops every single time, simply by using the science and technology you say they already have.
Yeah that would make more sense... but I forgot to mention these evil soldiers are all Nazis, which mean they're crazy enough to look at their twenty thousand people on Antarctica and plan to get to five billion by the end of the century... but thick headed enough to think that 'real soldiers of the Reich can be born naturally to a mother and father'... which means they trade the super space embryo tech in for steamrolling over feminism so hard that Sylvia Plath's corpse twitches.
It's improbable that your ice Nazis would be able to attain thier desired population, then. Not every embryo will implant. Of those that do, not every embryo will develop. Of those that do, a percentage will self-abort/miscarry. Of those that survive to term, a percentage will die during or shortly after birth and an additional percentage will be born or will become disabled in infancy. Of those that survive, a percentage will die or become disabled during childhood. Out of that fraction, there are those that will die or become disabled as teens. Your assumption of a perfect fertilisation, implantation, birth and mortality rate is more of a problem than your original desired population is. That's not even beginning to address the issues of repeated births and very young births on the women that would be carrying the babies. A lot of them will become infertile and or die. Many of them will experience complications that will be fatal for both the woman and the child she is carrying, so you'll lose them both, with no replacement. You will be looking at a decline in your population of fertile women and girls. As those your program doesn't kill directly and initially continue bearing, you will be looking at more and more unhealthy women and babies as the bodies of the women repeatedly giving birth also become increasingly prone to more and more severe and devastating complications. And the younger they start, the sooner those will begin to show up. Too, at the upper end of the age range you will begin to run into yet another set of co-morbidities for both woman and infant, a greater increase in "missed" implantations, miscarrages, premature births, low birth weights, and congenital defects. It can't be done the way you say you want to write your story, particularly in so short a time.
Yeah... but I think I'm still going to keep this number, because if the reader goes through this math, it will become quite apparent that this army of evil came out of a lot of young girls dying on the delivery table... which somehow makes the Nazis look even more evil. Though to make sure nobody rightfully calls BS on this, I can increase the initial population just a bit more to like 30,000-40,000 (any more and I will create another plot hole of that being a silly amount of people to pull out of the dying days of the third Reich), so there is enough implied baby and mother death to cause them to run away screaming but not too much to make them scatrch their head at that five billion number.
Yeah, I'm going to agree with @KatefromIowa that if they're not using some kind of sophisticated technology or medicine to be able to ensure that all women get pregnant the second it's possible and that those pregnancies are successful, those numbers get drastically lower. Even with assuming all of those things and sophisticated technology and medicine that also prevent any kind of widespread plague that I'm almost absolutely certain would happen, I could still only get the number to 142 million people after 100 years. So I would absolutely still run away screaming at the 5 billion number.
Honestly, I'll barely buy millions in 80 years flat.
Ok, so depending on the technology (it isn't hard to believe this is possible) they may be able to make sure women are not only constantly pregnant, but also having multiple babies at once. Some women naturally are prone to multiples pregnancies because their ovaries release a bunch of eggs at once instead of the usual one. Probably someone could carefully use hormones/drugs to force this effect on everyone. If each woman had ten sets of quadruplets in her life, that would kick up the population growth.