• booty [he/him]@hexbear.net
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    1 year ago

    I think there’s enough more than 8 billion humans that a stable population could recover. It’d take a while though.

    • Frank [he/him, he/him]@hexbear.net
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      1 year ago

      Yeah we only need something laughably small like 20k people to bounce back or something. I read somewhere we could have a survivable amount of genetic diversity with just 26 unrelated people but idk if that’s true.

      • booty [he/him]@hexbear.net
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        1 year ago

        I’ve read conflicting information on that over the years, and it seems entirely possible that the dumb math nerds who figure this stuff out aren’t completely certain about it. I’ve heard that 26 number before, I’ve also heard other numbers in the low hundreds and low thousands.

        Could all be discussions about different stuff that gets misunderstood / misrepresented, though. Like if you’ve only got 26 people to work with, you’d better hope nobody dies any time soon, especially not for example during childbirth and taking the baby out with them. There might be a certain number in the hundreds that generally minimizes the risks of random deaths and disease dooming humanity.

        Also you’ve gotta keep thorough records for at least a few generations and also enact some kind of tyranny to make people breed according to who is the least closely related. Man, this sounds like a fucking nightmare tbh

        Edit: It sounds like it could be a fascinating concept for a game, either like tabletop or video game or whatever, though. You’ve got a settlement made up of like 30 people, you’re the last humans left, don’t go extinct. Good luck.

        • Philosoraptor [he/him, comrade/them]@hexbear.net
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          1 year ago

          Assuming an average population, the most reasonable estimates I’ve seen for the “safe” margin are mostly around 1,000. It’s definitely possible to get by with fewer than that–there are isolated tribes with fewer than 100 members who have done just fine for long stretches–but it makes everything much riskier. Humans are k-strategists in terms of reproduction: we have small numbers of offspring, but invest a lot of resources into each one. Species like that tend to have higher thresholds for viable population size, because each instance of reproduction has more “significance” to the overall population, so a few suboptimal choices can have drastic impacts. However, unlike many other k-strategy species, we don’t tend to spread our populations out very thinly over vast distances, which helps ameliorate that somewhat. If your population were “optimal” (i.e. free of really bad recessive traits, all clustered together, very genetically diverse to start with, making “optimal” mate choices, etc.), you might be able to push the safe margin into the low hundreds. At that level, though, genetic drift starts to become a really big factor in evolution, so while it might be possible to sustain the species, the species might also get weird.