Tiny People

[Tvtyrant]

My brother and I were discussing how the new movie Downsizing would change space colonization, as ships with thousands of passengers could travel the stars in normal sized ships. This is also a common theme is sci-fi, with bottle cities and honey I shrunk the kids and the like.

Is it possible for a much smaller animal to retain human intelligence? If so how different would the brain to body ratio need to be?

[factotum]

I don't think it is possible, for one main reason: energy. The energy a small lifeform gains through its food is disproportionately spent on just surviving--for warm-blooded creatures like ourselves the possible heat generation is largely a function of volume, whereas the rate of heat loss comes down to surface area. If you halve the height you quarter the surface area, but the volume goes down to one-eighth, so the creature has to spend more effort in just maintaining body temperature. Since a complex brain is a very energy-hungry structure (around 20% of the total calories from our food goes to powering our brain), this would limit the brain size of the smaller creature.

[Tvtyrant]

So small animals radiate more of their body heat? How the heck do Krill live in the arctic then?

[georgie_leech]

So small animals radiate more of their body heat? How the heck do Krill live in the arctic then?

By not doing much; you'll notice coĺd areas don't tend to be the most lively environments But to my knowledge krill are cold blooded anyway, so they don't use energy directly the same way a mouse would.

[Knaight]

By not doing much; you'll notice coĺd areas don't tend to be the most lively environments But to my knowledge krill are cold blooded anyway, so they don't use energy directly the same way a mouse would.

The really big thing is that their biochemistry works at a low body temperature.

[Jay R]

If people can be shrunk in a way that makes it cheaper to ship them, then everything we know about Conservation of Energy is false. Therefore the most logical hypothesis is that it can't be done.

There is no clear correlation between brain size and intelligence in the range of most people's brains, but we believe that no (carbon-based life) brain 1/8 the size of a normal humans could contain human intelligence. And that's only a half-sized human. Getting down to somebody 1/10 our height would required a brain 1/1000 the size of our own, and there just wouldn't be room for that many nerve cells.

[aspi]

I think there is some clarification required. Is the original question

1. What implications would the possibility of downsizing humans have on space colonization? or
2. Is downsizing humans possible?

As other mentioned, the scientifically most likely answer to (2) is not possible. However, there is no reason not to discuss (1), even if the premise is ultimately untrue... and it seems to me that the original question was geared much more towards (1) than towards (2).

[Jay R]

I think there is some clarification required. Is the original question

1. What implications would the possibility of downsizing humans have on space colonization? or
2. Is downsizing humans possible?

As other mentioned, the scientifically most likely answer to (2) is not possible. However, there is no reason not to discuss (1), even if the premise is ultimately untrue... and it seems to me that the original question was geared much more towards (1) than towards (2).

I understand your point. Nonetheless, the correct answer to question 1 remains, "Since the possibility of downsizing humans is zero, it has no implications on space colonization."

[Yora]

By not doing much; you'll notice coĺd areas don't tend to be the most lively environments But to my knowledge krill are cold blooded anyway, so they don't use energy directly the same way a mouse would.

It's a bit more complicated with aquatic species. All nutients are getting eaten by something. In the water, all dead material eventually sinks to the bottom. All photosynthesis has to happen near the surface where there is light. So for life to continue, you need to have nutrients at the surface.
The problem is that warm water floats at the top and cold water sinks to the bottom, and all the warming takes place at the surface where sunlight can reach. So with warm surface water, you can't get the nutrient rich water from the bottom come up to the top.

This is not an issue in arctic waters, though. Water has maximum density at 4 degrees or so. In arctic regions the temperature difference between surface and bottom water can be completely negated so that it's possible for currents to move nutrient rich water from the bottom up to the surface where photosynthesis can transform them into organic matter. Which is why you have these stunningly massive swarms of krill in the arctics, which in turn feed equally humoungous numbers of fish. In comparison, tropical waters are barren deserts. Those white beaches? Completely dead. All the nutrients you have in tropical waters have swam there inside the bodies of migrating fish.

If people can be shrunk in a way that makes it cheaper to ship them, then everything we know about Conservation of Energy is false. Therefore the most logical hypothesis is that it can't be done.

There is no clear correlation between brain size and intelligence in the range of most people's brains, but we believe that no (carbon-based life) brain 1/8 the size of a normal humans could contain human intelligence. And that's only a half-sized human. Getting down to somebody 1/10 our height would required a brain 1/1000 the size of our own, and there just wouldn't be room for that many nerve cells.

To my knowledge, dwarfism does not result in reduced mental capacity, and there are some extreme cases of absolutely tiny people well below 80cm in height.

[Knaight]

To my knowledge, dwarfism does not result in reduced mental capacity, and there are some extreme cases of absolutely tiny people well below 80cm in height.

Dwarfism involves a fairly dramatic change in human proportions, and while it's a bit of a catchall term for several fairly distinct conditions involving very different biochemical problems leading to very different physiologies a common point is that brain size is very close to that of people without dwarfism.

Those people well below 80cm? Their brains are vastly larger than 1/8 the size of a typical human.

[Lvl 2 Expert]

I did some rough back of an envelope calculations on intelligent animals ones, comparing eq's and rough behavioral intelligence and such. My conclusion then was that a reasonable lower limit on human like intelligence given current earth biology would be around the size of a crow, half a kg or maybe a little more. (Both crowlike birds and parrots are already some of the smartest animals on earth, ballpark dolphins elephants and non-human apes, so it's not that weird a thought.) Of course, that size estimate is way too specific for a rough guess, but it could still be the right ballpark, depending on what the actual brainwise requirements for intelligence eventually turn out to be. The creatures would need relatively bigger brains than we have that use relatively more energy (50% of their total energy use wouldn't be that weird, compared to our 20% which is of course way less absollute energy, just relatively more), but being small is generally an energy efficient thing, one of the reasons smaller species tend to do better in major environmental disasters and tend to exist for longer than larger species. So energy requirements are not an immediate disqualifier. That is particularly true for this scenario: modern humans who can find enough food by going to the supermarket and who make their money with their brains voluntarily take a smaller body. The procedure itself is not feasible by a long shot for the foreseeable future (plus they're too small and their proportions are too much like those of a normal sized human), but the basic idea of a creature doing a brain based job living in a modern society being able to be smaller, not that weird. In fact, just imagine the kind of societies you could build if the apartments people needed were that much smaller. Add in some wings or drones or just little monorails strung up everywhere and we start solving traffic despite more people being packed in the same space, because the speed at which we commute won't go down as much as our size. A small person can still drive at highway speeds. So I'm in camp "gnomes are feasible, as long as they have big heads and they're roughly big enough to ride a large cat. (Also: an incredibly well trained cat.)

[Spojaz]

In zero G, a human contains a lot of useless meat. That meat has to be fed, housed, hauled out of gravity wells, exercised, and its waste products dealt with, in proportion to it's size. For long term space exploration or colonization, we certainly don't need to continue to use a body design built mostly to combat gravity.
Genetic engineering the human body to be smaller is an obvious step. Legs and balance muscles can be substantially scaled down, and the digestive system could be made much smaller, to more efficiently consume engineered food. Smaller blood mass could mean a simpler circulatory system, with higher tolerance to g-forces as a nice side effect. Smaller limbs mean slightly faster reaction times too.

To survive going back to our mother Earth's gravity well would require some serious prostheses, but that isn't going to be an insurmountable problem for a society willing to change bodies to fit it's environment.

[Tvtyrant]

If people can be shrunk in a way that makes it cheaper to ship them, then everything we know about Conservation of Energy is false. Therefore the most logical hypothesis is that it can't be done.
.

This statement befuddles me. If shrinking them was like antman and nothing else changed, sure. But I can put a mouse in a spaceship just fine. I am assuming you don't just get tiny atoms but that you are changed by the experience to fit your new role.

On that note, how much smarter is a person than a New Caledonian Crow?

[factotum]

To survive going back to our mother Earth's gravity well would require some serious prostheses, but that isn't going to be an insurmountable problem for a society willing to change bodies to fit it's environment.

I seriously doubt anything like this is going to happen until we already have established colonies in the other parts of the Solar System, though--you need the low or zero-gee habitats to exist before there's any point in engineering people to live there. Also, such people wouldn't be much use for colonising planets, which is what the OP was asking about.

[LordEntrails]

Sure, tiny people would make space colonization easier. Less mass requires less energy to accelerate it.

But, regardless of energy or other arguments, another simple reason tiny people won't happen is; You can't make a carbon atom (significantly) smaller. Same thing with a water molecule. So where to get a tiny human you have to drop something. You might be able to drop some of the space between molecules, but doubtful. Follow that same logic for brain cells, skin cells, etc.

It's a fun sci-fi theme, but its all fiction and no science.

[Tvtyrant]

Sure, tiny people would make space colonization easier. Less mass requires less energy to accelerate it.

But, regardless of energy or other arguments, another simple reason tiny people won't happen is; You can't make a carbon atom (significantly) smaller. Same thing with a water molecule. So where to get a tiny human you have to drop something. You might be able to drop some of the space between molecules, but doubtful. Follow that same logic for brain cells, skin cells, etc.

It's a fun sci-fi theme, but its all fiction and no science.

I think I may have badly worded the original question :P

My question is about the viability of dimunitive sentient life, not shrink rays. Shrink rays are purely science fiction.

To quote Farnsworth "That would require extremely tiny atoms. Have you priced those lately?! I'm not made of money, get off my back!"

[LordEntrails]

I think I may have badly worded the original question :P

My question is about the viability of dimunitive sentient life, not shrink rays. Shrink rays are purely science fiction.

To quote Farnsworth "That would require extremely tiny atoms. Have you priced those lately?! I'm not made of money, get off my back!"

"Naturally" tiny people would have benefits on space colonization. They would probably eat less mass, therefore they would need to carry less mass, and therefore consume less energy to do the same things (reach escape velocity, accelerate to speed, etc.

Would it impact settling on a planet? Other than dangers from native animals, probably not, since they wouldn't have to build full size stuff etc.

[Lvl 2 Expert]

Also, such people wouldn't be much use for colonising planets.

We send robots to space largely because a human brain is too expensive because of the space and food requirements of a full sized human. Having the same thinking power at a fraction of the weight, upkeep cost and pressurized space requirements would be pretty nice.

We're not going to have tiny humans, (or uplifted monkeys, which might be a more reasonable alternative) before we have computers that can do most stuff an astronaut can do, but if by some miracle of bioengineering a lab somewhere would roll out intelligent (and cooperative) squirrel monkeys tomorrow we could easily quadruple the amount of experiments running at any time in the ISS. Not to mention how much easier manned moon missions would become. An Eagle sized lander (as in "the Eagle has landed", not the bird) would be a decent long term habitat for such tiny astronauts, and as a bonus the return craft could be even smaller.

[Mastikator]

If we're finally willing to accept that humans need to be altered to be more efficient in space we should also consider replacing organs with cybernetic parts and replace as much of our metabolism with electricity as possible. Our metabolism is easily more efficient on Earth because of the ecosystem that sustains us but in space a solar panel and the Sun is easier to bring.

Organs that fail in low gravity should be replaced by mechanical organs that are designed for low gravity.

[Kail11]

It's a mind-**** of a concept. The environmental factors and everything...

[Tvtyrant]

If we're finally willing to accept that humans need to be altered to be more efficient in space we should also consider replacing organs with cybernetic parts and replace as much of our metabolism with electricity as possible. Our metabolism is easily more efficient on Earth because of the ecosystem that sustains us but in space a solar panel and the Sun is easier to bring.

Organs that fail in low gravity should be replaced by mechanical organs that are designed for low gravity.

I have pretty much always been okay woth cyborg and genetic alterations. For instance I think gills are extremely important both for Earth deep sea colonization and for space, as water filled space stations are essentially radiation proof.

If we could make sentient spider monkeys would their minimum wage be lower due to cheaper food and housing costs?

[Lvl 2 Expert]

If we could make sentient spider monkeys would their minimum wage be lower due to cheaper food and housing costs?

That's a social issue. A lot of people would probably stand behind the principle of equal pay for equal work, but the catch is you can go both ways from there, since a tiny person living in a tiny comfortable house eating tiny amounts of good food has the same standards of living as a large person having the large versions of those things, so technically their reward was equal. Giving them more would be discriminatory against proper sized humans. But, the more room you leave to pay small people less, the more of a disadvantage large people will have on the job market unless they're willing to work for less as well. It'd basically be a bigger more cluster****y version of the age old "immigrants willing to make lower wages" thing nobody has ever found a proper answer for.

And from there on you could speculate on racial (special? That doesn't work at all...) tensions. If there was another group of sentient beings, whether they're evolved crows, uplifted monkeys, tiny time travelers or something that isn't small and starts falling outside of the current discussion, they would become the most obvious outgroup for any tribal us vs them rhetoric. Whether they make the same wage but it's technically unfair or they make less and we don't have a job anymore, both of those would only make things worse. It's a cool thought experiment and there are probably already several good social science fiction books dealing with it, although I couldn't name any. The situation would be slightly better if people could be shrunk like in the movie that started the topic. If you really think it's unfair, just join them.

As long as their numbers stay pretty small, tiny persons/uplifted monkeys are only used for a few specialist industries like space exploration which doesn't suddenly bloom into a massive colonization attempt it can be solved either way and their shouldn't be too much fuzz about it.

(Yes, this is precisely the sort of thing I love thinking about.)

[Tvtyrant]

That's a social issue. A lot of people would probably stand behind the principle of equal pay for equal work, but the catch is you can go both ways from there, since a tiny person living in a tiny comfortable house eating tiny amounts of good food has the same standards of living as a large person having the large versions of those things, so technically their reward was equal. Giving them more would be discriminatory against proper sized humans. But, the more room you leave to pay small people less, the more of a disadvantage large people will have on the job market unless they're willing to work for less as well. It'd basically be a bigger more cluster****y version of the age old "immigrants willing to make lower wages" thing nobody has ever found a proper answer for.

And from there on you could speculate on racial (special? That doesn't work at all...) tensions. If there was another group of sentient beings, whether they're evolved crows, uplifted monkeys, tiny time travelers or something that isn't small and starts falling outside of the current discussion, they would become the most obvious outgroup for any tribal us vs them rhetoric. Whether they make the same wage but it's technically unfair or they make less and we don't have a job anymore, both of those would only make things worse. It's a cool thought experiment and there are probably already several good social science fiction books dealing with it, although I couldn't name any. The situation would be slightly better if people could be shrunk like in the movie that started the topic. If you really think it's unfair, just join them.

As long as their numbers stay pretty small, tiny persons/uplifted monkeys are only used for a few specialist industries like space exploration which doesn't suddenly bloom into a massive colonization attempt it can be solved either way and their shouldn't be too much fuzz about it.

(Yes, this is precisely the sort of thing I love thinking about.)

An interesting side issue would be labor division. A monkey construction worker wpuld be much weaker then a human one, while a monkey typist would be more efficient.

[Lord Torath]

Anyone see Disney's Zootopia? It kind of brought up the issue. Elephants get ginormous popsicles for the same price mice get tiny ones. Fox buys a ginormous one, splits it up and sells the multitude of tiny-size pops it makes to the tiny mammals at just under regular tiny-size price for a big profit. It's not the focus of the movie, though, so no possible solutions are discussed.

[Lvl 2 Expert]

Anyone see Disney's Zootopia? It kind of brought up the issue. Elephants get ginormous popsicles for the same price mice get tiny ones. Fox buys a ginormous one, splits it up and sells the multitude of tiny-size pops it makes to the tiny mammals at just under regular tiny-size price for a big profit. It's not the focus of the movie, though, so no possible solutions are discussed.

He's also selling it in a very upscale district to a bunch of what seems to be bankers. Plus smaller portions tend to cost relatively more in general.

But you're right, they do touch on roughly this topic in several places (labor division for instance is a big one). It's also just a plain awesome film in general.

[Vogie]

"Naturally" tiny people would have benefits on space colonization. They would probably eat less mass, therefore they would need to carry less mass, and therefore consume less energy to do the same things (reach escape velocity, accelerate to speed, etc.)

Theoretically, they'd also get larger over time. We know from NASA's most recent experiment that, after a year in space, Scott Kelly returned home 2 inches taller than his identical twin. That information was extrapolated in The Expanse series, where those grew up and lived in the Asteroid Belt were taller and lankier due to the lower gravity.

[factotum]

Theoretically, they'd also get larger over time. We know from NASA's most recent experiment that, after a year in space, Scott Kelly returned home 2 inches taller than his identical twin. That information was extrapolated in The Expanse series, where those grew up and lived in the Asteroid Belt were taller and lankier due to the lower gravity.

It's not quite the same situation. Astronauts get taller in space because gravity is no longer compressing their spines and other joints, so they expand. People who are born and raised in low gravity would get very tall and lanky because their bones would actually grow longer. The difference being, when Scott Kelly had been back on Earth in regular gravity for a while he would return to his previous height, whereas people born and raised in low gravity would be just as tall and lanky on Earth as they are in space.