# Tag Info

### Russian Dolls - How do they reproduce?

Through selective breeding and misplaced import laws, we only ever get to see Russian dolls that are "aesthetically pleasing". In the wild, it is relatively common to get a "double-yolker" - that is, ...
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### If everyone in the world disappeared except 35 random people, how long would it take for one of them to realize they're not alone?

Assuming that it's purely random, let's consider where these people would probably be. Taking the percentage of the population each country represents, we get: China: 18.2% = 6.37 people India: 17.5% ...
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### If everyone in the world disappeared except 35 random people, how long would it take for one of them to realize they're not alone?

It's HF radio, or nothing The odds of anyone meeting again are almost exactly equal to the odds of at least two being either radio hams, or able to learn the skills from books. The population ...
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### Russian Dolls - How do they reproduce?

In the deepest, darkest, hidden places in the forest dwell the Queen Dolls. Rarely seen, these creatures resemble a normal Russian Doll only at the tops of their vast, misshapen bodies - their lower ...
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### Russian Dolls - How do they reproduce?

Actually, there is an organism on earth that is vaguely similar to the Russian dolls that you describe. The volvox: Individual volvox cells, a kind of freshwater algae, reproduce in the conventional ...
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### How poor does Elven fertility need to be in order to keep the ratio of humans to elves constant?

The different causes of death are the biggest issue here. Humans will lose a lot of children to disease, elves don't seem to suffer from this Humans lose fertility early then die fairly young, again ...
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### How big can a town get before everyone stops knowing everyone else?

The number you are looking for is not Dunbar's Number Dunbar's number is about how many relationships you can maintain, but does not directly dictate the "sense" of knowing everyone. ...
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### How many people are necessary to maintain modern civilisation?

I'm going to respond to this with a framing challenge, because as it stands I think you're asking the wrong question. The issue is that the modern industrial world is a product of population DENSITY ...
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### How big can a town get before everyone stops knowing everyone else?

The number you are looking for is Dunbar's Number. It is well-known for most primates, but only approximately for humans (between 150 and 250). Humans of course have prodigious memory, and might be ...
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### If everyone in the world disappeared except 35 random people, how long would it take for one of them to realize they're not alone?

This is an interesting question. Obviously, just walking about and hoping to meet someone is fruitless, the chances are just ridiculous. What you would want to do is communicate. Now we know how many ...
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### Why would a country with high population suffer from low manpower?

"The events are set in a late renaissance like world, minus the gunpowder." Fine. Let's take this as given, and let's assume that by "late Renaissance-like" we understand western European Renaissance,...
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### What would be a logical reason to explain space based families having more children than an earth based one

There's not a lot to do in space, so bored people in close quarters resort to what they always do, and have large families as a result. The small families that are the norm in today's developed world ...
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### Elf-like race: What could prevent overpopulation?

Low natality rates. They would live long, but procreating a child is a very rare event for all couples. That should balance the lack of aging, if deaths due to other reasons are not too frequent.
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### If everyone in the world disappeared except 35 random people, how long would it take for one of them to realize they're not alone?

(This answer supposes that electricity and the internet survives for a day or two) Either a couple of days, or many months, if ever. CALLING OUT TO ALL SURVIVORS Hello! Everybody in the world has ...
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### My Medieval kingdom has birth control, why is the population so high?

A Lack of Birth Control Wasn't the Cause of Large Families As one commenter already pointed out, the reason people had large families in the Middle Ages wasn't because they couldn't avoid it; rather, ...
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### If everyone in the world disappeared except 35 random people, how long would it take for one of them to realize they're not alone?

I figured, since a lot of people are bringing up the Birthday Problem, I'd add a separate answer just for discussing it. Simply put for those not familiar with it, the idea is that based on ...
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### In theory, could all mammals be wiped out by a single pathogen?

Yes, but not in the way you are thinking. One way this could happen is if some killer fungus starts growing unchecked throughout the planet, on land and sea. By killing all plant life it would destroy ...

### What would be a logical reason to explain space based families having more children than an earth based one

Attrition Also one of the reasons rural medieval families were usually large ones. Because space stations represent the frontier, the most hazardous jobs and the workforce handling those jobs would ...
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### Russian Dolls - How do they reproduce?

Regenerate the top part. The splitting doesn't actually kills the doll - just its bottom half. The bottom half becomes a nest for the little doll that was gestating on the inside of the "mother doll"...
• 9,094
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### What is the longest time Humanity could be sterilized for without causing extinction?

Assumption #1: Somewhere between 40 and 50 years. Any girl babies just conceived before the Curse was thrown down will have somewhere between 40 and 50 years before menopause sets in and they will no ...
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### The nation without villages

An easy way to justify large cities-only settlements is to have specific requirements that can't be scaled down too easily. One example would be to need a domed environment, easier to maintain in ...
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### Russian Dolls - How do they reproduce?

Budding and out-growing. Budding: each outer doll, once in a while, produces a bud, which in this case is a tiny Russian doll. Once it detaches from the mother body, it starts living on its own. Out-...
• 291k
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### How many human beings are/were there?

107 Billion according to the Population Reference Bureau. Details Here Must warn that this can only be guessed and is based on arbitrary definitions of human. What we call hominids (i.e., humans) ...
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### How could names plausibly change over several generations of humans living in a space station on another planet?

Living in a sealed environment requires everybody to be educated. You can't risk someone dumping lubricants in the toilet because that's an easy way to get rid of them, etc. Education means literacy, ...
• 117k
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### How to cause an exodus from the west coast of the United States inland?

San Andreas makes big boom! many little booms So, the Big One is finally about to happen: Scientists have seen the pressures spike, all the signs are screaming DOOM! Fortunately, just hours from ...
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### What are some reasons for the population of a small, relatively unremarkable area to suddenly boom?

Villages tend to explode in population because... Discovery of a local natural resource. The town becomes a center of trade (multiple trade routes, change in resources elsewhere). The town becomes ...
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### Is a population of people with eternal youth sustainable?

This idea that people with eternal youth would be constantly reproducing is not necessarily accurate; nor is the idea that producing any more than 2 children per couple going to result in population ...
• 54.1k
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### Elf-like race: What could prevent overpopulation?

Aging is not necessary to maintain their low population. No population can grow without limit, and in the animal kingdom, most animals die before they would otherwise die of extreme old age. These ...
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### Would a kingdom allow creation of new settlements?

Historical context of population growth Population expanded significantly in the middle ages, between the low after the ravages of the Justinian Plague of 541-542 to the high middle ages peak of ~...
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