# Would space colonies see us develop new ethnicities and physical/mental adaptions to those places?



## DAgent (Jul 20, 2022)

A couple of thoughts that occurred to me while reading up on O-Neil cylinders and space wheels as possible homes in the stars, what would happen to how the people there develop? Assuming the gravity in such places are kept to the standard 1G we have on Earth, I can't see much need for adaption as we'll have made the "world" to suit us in those cases. But could simply being in space have some effect that makes us change in some way?

Then there's the idea of ethnicities. I'm pretty sure someone somewhere might try to setup a colony that is only for one specific ethnic group, they might use some creative wrangling of language to try to pretend that's not the way it is, but I can still see it happening. In such a place, would the residents end up going through some sort of ethnic change anyhow, in a similar way to how ancients humans who left Africa millions of years ago, changed and adapted to their new homes and the environmental changes they found there?

I think it goes without saying that a colony filled with people of every ethnicity will end up intermingling and end up with new ethnicities due to that. And I can imagine that after a few generations the cultural expansion will mean they might have a very different take on say art, religion, music, then what their founders had. How much richer in culture would such a colony be?

Then throw in the idea of living on planets, either in sealed environmentally domes, or terraformed worlds, would the same happen there?


----------



## Bramandin (Jul 20, 2022)

I think that there would be an ethnic melting-pot where some traditions are lost while others are blended.  The language would drift, the culture would be its own, you'd have Klingon be a cultural marker instead of a genetic one.


----------



## THX1138 (Jul 20, 2022)

I have a similar situation in my novel. There is an Aliance of some Earth cultures that are just what you are talking about. After 100 years, the united earth forces think that the Aliance has become a waring colony against Earth, (they are not) When they meet, the appearance, language and customs of the Aliance has changed to the point of becoming a new culture. One could say 'Alien' in their own right.

But when you look are cultures even here on earth, we can see this too. Even today you can see it. The Bahamas and the VI's are a good example of culture, language and definite signs of race blending. There are many places on Earth one could study this. But in a space colony, I think it would be an obvious given.


----------



## Vladd67 (Jul 20, 2022)

For an earth example just compare the US with the rest of the world. Originally a colonial possession it has evolved into a society with it's own cultures and beliefs.


----------



## Toby Frost (Jul 20, 2022)

I think it could depend a lot on how the colonists see themselves and how they want to be. They might end up deliberately not changing, like Victorians in the Raj - however, this probably requires a native population to react against. A war or similar struggle might cause the colonists to deliberately forge their own identity, like post-War of Independence USA or post-WW2 Australia (note that the first is colony v homeland, while the second is after a war where colony and homeland were on the same side but had different priorities). If they feel that they're being picked on or ignored, they will probably create a separate identity faster.

I vaguely remember the TV show of The Expanse giving the Belters distinctive accents, a bit like South Africans. There are plenty of stories where people brought up underground, in space etc suffer from agoraphobia, which might be a distinctive trait of colonists growing up in stations. There might also be odd customs relating to the local environment, like the Fremen spitting to make an agreement more binding. And that's without deliberate genetic modification.



DAgent said:


> Then there's the idea of ethnicities. I'm pretty sure someone somewhere might try to setup a colony that is only for one specific ethnic group



Humans being what they are, I think this would be very likely, not just in terms of race, but religion, politics, even sex. Such people would probably think of themselves as the new Pilgrim Fathers, but it could easily turn into an inbred tyranny. Which raises the issue of what happens if there isn't enough genetic variance to prevent conditions appearing. I don't know enough about the science of that to really comment.


----------



## Wayne Mack (Jul 20, 2022)

Due to the spinning nature, people would need to adjust movements based on the direction of travel, they would need to adopt 'sea legs.' This would be even more pronounced with any sort of ball sports. A thrown or rolled bar would curve when thrown at an angle to the direction of spin. A ball thrown in the direction of spin would have a (probably slight) drop to it, while one thrown in the opposite would have a rise. The direction of fields, courts, playing surfaces, etc. would likely need to be specified, else the home team would have a significant home field advantage. Certainly within a generation, people would adapt to these forces and would likely feel unsettled if they returned to Earth.


----------



## Swank (Jul 20, 2022)

There is no reason a space tube would develop different ethnicities than blended societies like most Western nations already have. Virtually all the ethnic blends you are likely to ever have can be viewed on the street of any metropolitan area today.

There's also little reason that there would be extreme cultural shifts given shared media and instantaneous communication.


And there certainly isn't likely to be any sort of evolution. People have to die before breeding for natural selection to work. If people have an inner ear problem (unlikely on something as large as an O'Neil), they will take drugs for it.


Immunity would be one of the largest issues, as the colonies would likely have quarantine processes to prevent SARS or flu coming aboard. Over time that could be a problem.


----------



## Bramandin (Jul 20, 2022)

Toby Frost said:


> I don't know enough about the science of that to really comment.



I heard about the 50/500 rule, but I imagine it depends on factors like if there is a mutation where they have to decide whether to practice eugenics or learn to deal with it.  I think there was a place where descendants of one person were deaf to high-pitched sounds and it wasn't a problem until they tried to watch Mickey Mouse cartoons.


----------



## Le Panda du Mal (Jul 20, 2022)

I think some of us are thinking about ethnicity as a genetic thing where I would argue language and culture are far more important. For instance, the spread of Arabic language and Islam resulting in disparate ethnic groups in the MENA region becoming "Arabs" over centuries. Likewise many Turks in Turkey today are genetically closer to Greeks or Armenians than to central Asian Turks but that isn't terribly relevant as far as identity goes. I think space colonies would inevitably form separate ethnic identities over time.


----------



## Wayne Mack (Jul 20, 2022)

Given the smaller population size relative to Earth, I can see a space station peoples evolving into a distinct group relative to Earth-based ethnicities. There may also be a concern about interbreeding. I can also see the challenges of traversing between the cylinders as enough of a issue that each might evolve differently. I also wonder if there is a danger of loss of immunities making travel to Earth risky. Lastly, I could see the evolution of a bacteria or virus that could be near fatal to the community.


----------



## Montero (Jul 20, 2022)

In the forty ish years Germany was divided into East and West there were divergencies in vocabulary with East gaining Russian words and West Americanisations.


----------



## Aknot (Jul 21, 2022)

Simple answer: mainly depends on how long they are isolated. 

I’m not an biologist but I know enough to say that given enough generations in a new environment - however different from earth - there would be genetic differences. However, most likely an cultural change would be much swifter and, possibly, more significant. In 10,000 years the humans would have adapted in various ways, but still very much be humans. Culturally they could be radically different. 1,000,000 years they would probably have evolved through several stages of “homo” (Homo Astra, or whatever the non-pig Latin version is).


----------



## Aknot (Jul 21, 2022)

Consider the size of the population as well. Partially for reasons if generic change and diversity, but also survival. For a project I looked up various scientific guesses and they arrived at at least 10,000 people to avoid the risk of catastrophic “failure” for the group. A very possible  scenario for an isolated group over a long period of is also extinction…


----------



## Robert Zwilling (Jul 21, 2022)

The Expanse story ran it with some physical body differences for people born in different places in the solar system, but the attitudes and behaviors were all on the same page, no changes there, probably a good guess. Tastes in the arts might depend more on what is available at the time than anything else. The biggest change would seem to be going back in time, to when a single event could wipe out the entire group, such as an infection that can't be cured.


----------



## Swank (Jul 21, 2022)

Robert Zwilling said:


> The Expanse story ran it with some physical body differences for people born in different places in the solar system


To be fair, the differences were only due to the amount of gravity different people grew up in and how that affected their bodies and height. It wasn't a genetic thing.


----------



## JunkMonkey (Jul 21, 2022)

DAgent said:


> How much richer in culture would such a colony be?



It is entirely possible that - as happens in societies here on Earth - a dominant repressive set of ideas (any of a number of fundamentalist religions being an obvious example) might quickly stifle any richness and variety cross cultural mingling might bring.


----------



## Toby Frost (Jul 21, 2022)

I agree: a lot of this depends on the ideology of the colonists.


----------



## Swank (Jul 22, 2022)

I think we might be over-emphasizing the isolation of a space colony. Communications are easy, as is travel to other colonies or nearby airless worlds. Someone in an O'Neil will be much more cosmopolitan and worldly than a someone from Peru or North Dakota.

There's no obvious reason that an O'Neil would be built far away from other colonies or a terrestrial base. It is not a space ship.


----------



## Bramandin (Jul 22, 2022)

Swank said:


> I think we might be over-emphasizing the isolation of a space colony. Communications are easy, as is travel to other colonies or nearby airless worlds. Someone in an O'Neil will be much more cosmopolitan and worldly than a someone from Peru or North Dakota.
> 
> There's no obvious reason that an O'Neil would be built far away from other colonies or a terrestrial base. It is not a space ship.



I can just imagine that the local culture becomes homogenized, but then you get this weirdo who picked up a subculture like furry up from the internet.


----------



## Serendipity (Jul 22, 2022)

Oh dear - I may be out of step with the rest of the SF community on this one - but history has shown local environments affect cultures. A good example is my grandmother who lived in the heart of Europe well away from the sea mentioned one day that you could see the trees on the distant hilltops clearly and that meant rain was on its way. Huh? Where were the clouds? But she was right. The rain did come by the evening. People learn the quirks of their local area and act accordingly. 

If you have people living on asteroids, moons and even planets, they will learn and react to local phenomena. From there on in, Darwinian evolution will produce people who are better adapted to the environment e.g. able to cope with lower gravity more easily. It is but a short step from there to changes in culture.

Quite frankly so many writers severely underestimate the impact of the local environment off Earth. I certainly used to until I decided to write a novel set of Miranda... but that is another story!


----------



## Swank (Jul 22, 2022)

Serendipity said:


> If you have people living on asteroids, moons and even planets, they will learn and react to local phenomena. From there on in, Darwinian evolution will produce people who are better adapted to the environment e.g. able to cope with lower gravity more easily. It is but a short step from there to changes in culture.


This is simple not how evolution works. Natural selection is a process that requires individuals with better adaptations to survive to reproduce while the less adapted individuals die before they produce children. There is no natural selection forces at work when no one is dying. Modern humans don't die off when they have bad eyesight because they walk into traffic - they get glasses and have kids.

Evolution is largely misunderstood as a process. Aside from immunology, human evolution has largely been on hold for several thousand years because we substitute technology and social services for deadly natural selection.


----------



## Serendipity (Jul 22, 2022)

Swank said:


> This is simple not how evolution works. Natural selection is a process that requires individuals with better adaptations to survive to reproduce while the less adapted individuals die before they produce children. There is no natural selection forces at work when no one is dying. Modern humans don't die off when they have bad eyesight because they walk into traffic - they get glasses and have kids.
> 
> Evolution is largely misunderstood as a process. Aside from immunology, human evolution has largely been on hold for several thousand years because we substitute technology and social services for deadly natural selection.



One of my recent investigations that I found so fascinating was how good people's eyesight was from various parts of the world. There are differences by region (especially how well people can differentiate green shades even these days), which shows evolution in reaction to environment is ongoing. 

I suspect we are just not realising how evolution is affecting us these days because we don't know what to expect in reaction to the availability of medicine and technology. Without going in details, looking at my family history rather confirms it for me.


----------



## Wayne Mack (Jul 22, 2022)

As the level of light and radiation exposure would assuredly be consistent throughout the space station, I could see skin tones trending to a common level. To be viable, I would assume that a significant portion of the station residents would need to be agricultural workers (this might be offset through mechanization). This would mean they would also have long periods of exposure to light and ultraviolet rays in particular. Lighter skin tones would provide greater risk of skin cancers and lost productivity to things like sunburn. Given a relatively small population size, darker skin tones than absolutely needed would also be diminished over time. I am not sure whether this would constitute an ethnicity, but a could see an isolated station developing its own skin tone.


----------



## JunkMonkey (Jul 22, 2022)

Swank said:


> This is simple not how evolution works. Natural selection is a process that requires individuals with better adaptations to survive to reproduce while the less adapted individuals die before they produce children. There is no natural selection forces at work when no one is dying. Modern humans don't die off when they have bad eyesight because they walk into traffic - they get glasses and have kids.
> 
> Evolution is largely misunderstood as a process. Aside from immunology, human evolution has largely been on hold for several thousand years because we substitute technology and social services for deadly natural selection.



As people, especially women, take control of their fertility and have fewer children and have them later in life - I was reading today that the high school population of Britain/UK/England & Wales* is going to fall by a million over the next decade - then that is going to have some knock on genetic effect.  It's maybe not 'natural selection' but a self-selection. 


* - I can't remember which (if it was specified at all).


----------



## Bramandin (Jul 22, 2022)

JunkMonkey said:


> As people, especially women, take control of their fertility and have fewer children and have them later in life - I was reading today that the high school population of Britain/UK/England & Wales* is going to fall by a million over the next decade - then that is going to have some knock on genetic effect.  It's maybe not 'natural selection' but a self-selection.
> 
> 
> * - I can't remember which (if it was specified at all).



I had to turn off Idiocracy, but that was the basic premise.  It showed two smart people waiting to have children until they were in a good place to raise it, waiting too long, while a redneck was being genetically successful through the scattershot method.


----------



## Robert Zwilling (Jul 22, 2022)

There is the case of the identical twins, one lived on the space station for a year with a restricted diet and predictable life style, the other lived it up on Earth doing whatever he wanted to and eating whatever he wanted to. Both twins had space experience, the one on the station had 520 days in space, 340 of that on the station, the other one had a total of 54 days in space.

When the space bound twin came back to Earth there were noticeable changes in some gene markers and chromosomes. There were also other biochemical changes. Most of the changes reverted back to normal once the twin was back on Earth. 

Space does cause genetic changes. Just living on Earth also causes genetic changes, so it is normally hard to see what caused what to change. Exposure to certain substances or existence in particular climates do cause genetic changes in people. The twins provided a unique data set that does show changes, but can't be extrapolated in general to everyone because there were only 2 people in the study.

One thing that seems to happen generally to people in space is that their telomeres in some types of cells get longer. Which is normally a good thing, it could be related to a longer life. The cells with longer telomeres sort of live longer. Just about everyone on Earth starts out with longer telomeres which shorten over their lifetime. Changes in telomeres length in white blood cells have also been documented in a set of twins both on Earth the whole time. One climbed Mt Everest and the other didn't. 

Just because the telomeres get longer, which allows a cell to last longer, isn't always a good thing. By allowing a cell to outlive its standard time frame, there is a greater chance of mutations happening, some of which might not be beneficial.


----------



## Swank (Jul 22, 2022)

Wayne Mack said:


> As the level of light and radiation exposure would assuredly be consistent throughout the space station, I could see skin tones trending to a common level. To be viable, I would assume that a significant portion of the station residents would need to be agricultural workers (this might be offset through mechanization). This would mean they would also have long periods of exposure to light and ultraviolet rays in particular. Lighter skin tones would provide greater risk of skin cancers and lost productivity to things like sunburn. Given a relatively small population size, darker skin tones than absolutely needed would also be diminished over time. I am not sure whether this would constitute an ethnicity, but a could see an isolated station developing its own skin tone.


Have you ever seen the typical Caucasian farmer? How dark were they?


----------



## Swank (Jul 22, 2022)

Robert Zwilling said:


> There is the case of the identical twins, one lived on the space station for a year with a restricted diet and predictable life style, the other lived it up on Earth doing whatever he wanted to and eating whatever he wanted to. Both twins had space experience, the one on the station had 520 days in space, 340 of that on the station, the other one had a total of 54 days in space.
> 
> When the space bound twin came back to Earth there were noticeable changes in some gene markers and chromosomes. There were also other biochemical changes. Most of the changes reverted back to normal once the twin was back on Earth.
> 
> ...


"Space" doesn't do anything on its own. Microgravity and radiation do things to people. But an O'Neil is built to provide earth level gravity and radiation levels.


----------



## Le Panda du Mal (Jul 22, 2022)

Swank said:


> This is simple not how evolution works. Natural selection is a process that requires individuals with better adaptations to survive to reproduce while the less adapted individuals die before they produce children. There is no natural selection forces at work when no one is dying. Modern humans don't die off when they have bad eyesight because they walk into traffic - they get glasses and have kids.
> 
> Evolution is largely misunderstood as a process. Aside from immunology, human evolution has largely been on hold for several thousand years because we substitute technology and social services for deadly natural selection.



Yeah, when people talk about human evolution, I have to ask, what traits are being selected for? And the answer seems to be "just about everything." All kinds of people are reproducing or not reproducing for all kinds of reasons.


----------



## Swank (Jul 22, 2022)

JunkMonkey said:


> As people, especially women, take control of their fertility and have fewer children and have them later in life - I was reading today that the high school population of Britain/UK/England & Wales* is going to fall by a million over the next decade - then that is going to have some knock on genetic effect.  It's maybe not 'natural selection' but a self-selection.
> 
> 
> * - I can't remember which (if it was specified at all).


This is an example among many of selection processes that affect populations. It just isn't a natural selection process that results in beings that are better adapted to their environment as has been suggested repeatedly in this thread.

It is similar to how dwarfism is common in the Amish populaton or Kleinfelter's in the Ashkenazi. They don't produce net population adaptations over time that diverge from the base genome or increase fitness.


----------



## Swank (Jul 22, 2022)

Serendipity said:


> One of my recent investigations that I found so fascinating was how good people's eyesight was from various parts of the world. There are differences by region (especially how well people can differentiate green shades even these days), which shows evolution in reaction to environment is ongoing.
> 
> I suspect we are just not realising how evolution is affecting us these days because we don't know what to expect in reaction to the availability of medicine and technology. Without going in details, looking at my family history rather confirms it for me.


Or, we are unaware of the environmental circumstances that promote good vision in developing children. Which is much more likely for the reasons stated. 

I have excellent vision. It is not advantageous in the competition to reproduce, nor was it for my father.


----------



## Bramandin (Jul 22, 2022)

Swank said:


> It just isn't a natural selection process that results in beings that are better adapted to their environment as has been suggested repeatedly in this thread.



This argument backs up why aspergers isn't the next step in human evolution, it's nature throwing things in randomly to see what sticks.  (Dark moth/Light moth.  There was a decade or so where the environment favored the previously less-fit individuals.)  It doesn't matter that a lot of autistics are set up for STEM when the selection pressure is social aptitude and not everyone can stay out of the uncanny valley even with effort.  Even if society accommodated us enough to be personally successful, there are barriers to being genetically successful and that's ignoring the eugenics campaign.


----------



## Robert Zwilling (Jul 22, 2022)

Gravity on Earth has a more or less constant attraction over short distances like a few miles. Gravity loses about 10 percent over 300 km. That's around 180 miles. That means the pull of the artificial gravity for centripetal force will decrease a lot faster over a shorter distance. The radius of O'Neill cylinders we are talking about are considerably smaller than that. Or we can say that they are hundreds of miles in diameter and have the decrease of artificial gravity as you approach the axis a minimal value. 

Gravity has thousands of unique properties while centripetal force is only a subset of gravity. I am sure that the effects of artificial gravity and real gravity are not identical on living things especially when the difference is much greater over a shorter distance. Crystals might even grow differently where centripetal force is dominant over gravity. There are articles about growing crystals in centrifuges, but they are about improving crystal growth using high speed. The crystals can come out different than those grown in regular gravity. I would say the the lessening of the artificial gravity as you move towards the axis could also have dynamic effects on the way all kinds of particles, living or inert, interact.

To minimize radiation, just build it inside a huge radiation proof shell. The power required to operate such a construction would already be astronomical so creating an artificial light source to light up the inside would be no big deal.

The problems would come during the development of the cylinders, which would start small and have all sorts of problems. After that, if it could be made big enough and if energy wasn't an issue, it would be a walk in the park.

Apparently people would be living a long time in it, so some sort of population control might be required. Unless it was self replicating and could grow new sections as required. The resources would come from a nearby planet which would be totally inhospitable, which is why people would be stuck inside a giant rotating cylinder in the first place.


----------



## Swank (Jul 23, 2022)

Robert Zwilling said:


> Gravity has thousands of unique properties while centripetal force is only a subset of gravity.


I would love to read a scholarly article that supports this supposition. Acceleration is acceleration. At the size of an O'Neil, there would be virtually no difference in G between your head and your feet to create unique biological outcomes.


----------



## Wayne Mack (Jul 23, 2022)

Swank said:


> Have you ever seen the typical Caucasian farmer? How dark were they?


Consider the differences in skin tone between northern Europe peoples and populations that live along the equators. I would expect that the conditions inside a space station would tend towards tropical, i.e., long periods of light with  lower levels of filtering. This also might affect eye shape.


----------



## JunkMonkey (Jul 23, 2022)

Wayne Mack said:


> This also might affect eye shape.



why?


----------



## Bramandin (Jul 23, 2022)

JunkMonkey said:


> why?



Maybe they're thinking that Epicanthal folds can help protect the eye from excess light?  I have hooded eyes and being able to pull my eyebrows down over the sockets can really help with bright conditions.

Anyway @Wayne Mack evolution doesn't set out to fix problems, it's that people who randomly have an advantage pass it on.


----------



## Swank (Jul 23, 2022)

Wayne Mack said:


> Consider the differences in skin tone between northern Europe peoples and populations that live along the equators. I would expect that the conditions inside a space station would tend towards tropical, i.e., long periods of light with  lower levels of filtering. This also might affect eye shape.


This is wrong on several counts. First, dark skin came before light skin. Light skin was an adaptation Europeans received that probably allowed them generate sufficient vitamin D, despite short winter days and full coverage clothing. This is what the direct ancestors of modern Britons looked like, 10,000 years ago:








Second, plenty of lighter skinned people live in areas with intense, direct sunlight. And they have survived because people have technology - like sleeves and hats - that prevent being damaged by the sun.

Third, we aren't talking about abandoning animals inside a glass space tube. A space station can have filtering windows that block the most harmful parts of the spectrum. It will also have clothes for its occupants, and medicine to deal with things like sunburn or cancer.

Which brings us once again back to number four:  Evolution doesn't work that way. For light skinned people to be selected against, those light skinned people would have to die in large numbers prior to reproducing compared to their dark skinned neighbors. Do you know of anyplace in the last 5000 years where light skinned people died off due to sunburn? Do you think the many light skinned occupants of Miami or Cuba or Sicily are dying in droves in their teens? Or do those people use technology like roofs, hats, sunscreen to moderate their sun exposure?


Humans no longer adapt to their environment - they adapt their environment to their needs. The way many of these posts have been going, I'm surprised no one has suggested that humans would naturally be able to survive in vacuum since it is right outside the space station.


----------



## Le Panda du Mal (Jul 23, 2022)

Yeah I feel like we’re dealing with a “giraffes have long necks because their ancestors kept stretching them” school of evolution. Which is not how natural selection works.


----------



## Robert Zwilling (Jul 23, 2022)

Most of the discussion is about living in perfect space structures with everything needed for a normal existence. Getting there is another story, and even not everyone will have the same opportunities. It takes a long time to get there.

As people start to move off Earth, they are going to be living in all sorts of structures in space, from small stations to big O'Neill cylinders. Not everything is going to be 100 percent shielded. People being people, are going to be exposed to all kinds of conditions with all kinds of results. For the space structures in our solar system, the farther away from the sun they get, the more likely they will probably have artificial lightning. For that matter, not every O'Neill cylinder is going to be parked next to a bright star. A window that only lets through visible light while blocking out harmful radiation would be standard on big operations but might be luxury on smaller operations. 

Some of the best shielding right now is water or cement, neither is currently practical for our capabilities. Heavy metal shielding creates secondary particles from the collisions which can be worse than the initial radiation if it is not thick enough, which creates a weight problem. The space station uses the Earth's natural shield for blocking radiation and for the sleeping quarters, a lightweight polyethylene plastic, called RFX1, which is composed entirely of lightweight carbon and hydrogen atoms is used. For now, it turns out for practical purposes, plastic works better than aluminum.


----------



## Bramandin (Jul 23, 2022)

Robert Zwilling said:


> People being people, are going to be exposed to all kinds of conditions with all kinds of results.







Though if we're going to go into gene modification, people designed for microgravity are probably going to have feet that can grip.


----------



## Swank (Jul 24, 2022)

Robert Zwilling said:


> Most of the discussion is about living in perfect space structures with everything needed for a normal existence. Getting there is another story, and even not everyone will have the same opportunities. It takes a long time to get there.
> 
> As people start to move off Earth, they are going to be living in all sorts of structures in space, from small stations to big O'Neill cylinders. Not everything is going to be 100 percent shielded. People being people, are going to be exposed to all kinds of conditions with all kinds of results. For the space structures in our solar system, the farther away from the sun they get, the more likely they will probably have artificial lightning. For that matter, not every O'Neill cylinder is going to be parked next to a bright star. A window that only lets through visible light while blocking out harmful radiation would be standard on big operations but might be luxury on smaller operations.
> 
> Some of the best shielding right now is water or cement, neither is currently practical for our capabilities. Heavy metal shielding creates secondary particles from the collisions which can be worse than the initial radiation if it is not thick enough, which creates a weight problem. The space station uses the Earth's natural shield for blocking radiation and for the sleeping quarters, a lightweight polyethylene plastic, called RFX1, which is composed entirely of lightweight carbon and hydrogen atoms is used. For now, it turns out for practical purposes, plastic works better than aluminum.


Plastic works better than aluminum because hydrogen provides the best shielding. Polyethylene might be good for thin walls, but to build multiple large O'Neils you might be looking at capturing asteroids of comets. At that point you have fairly large amounts of ice to use as shielding.

And you probably mainly need it for the sun pointing nose of the station.


----------



## JunkMonkey (Jul 24, 2022)

Bramandin said:


> Though if we're going to go into gene modification, people designed for microgravity are probably going to have feet that can grip.



and go barefoot all the time? Or were you thinking of opposable big toes? in which case shoes would have to look like gloves. And if you were going to go that far, wouldn't it be logical to make the whole foot more hand-like, and the ankle more wrist-like, with the ability to hold, twist and manipulate (pedipulate?) things?


----------



## Bramandin (Jul 24, 2022)

JunkMonkey said:


> and go barefoot all the time? Or were you thinking of opposable big toes? in which case shoes would have to look like gloves. And if you were going to go that far, wouldn't it be logical to make the whole foot more hand-like, and the ankle more wrist-like, with the ability to hold, twist and manipulate (pedipulate?) things?



The modifications would probably depend on whether the line is going to be designed to always be in microgravity or if their children are going to have the option of living on a planet.  Go full ape-foot and they wouldn't be able to walk far without support even if their muscles are good enough.  Then again with prosthetic technology the way it is, someone with feet that hamper them could have them removed and replaced.  Or they might be able to turn them into a chimera so that limb-regeneration technology can give them a foot suitable for where they want to live.


----------



## MaxRelaxman (Jul 24, 2022)

I was thinking about this, except more culturally recently. Ethnically people would just blend because they live closer together. There's only so much room, even on an O'Neil cylinder. Like other people have mentioned I don't think you'd see physiological differences unless people are living on different planets. So Martians would be taller than Earthers, but shorter than Lunies.
One thing I think is different from the Expanse is that I don't see people living on asteroids, maybe next to them in space stations but unless you're going to change the rotation of an asteroid in live in it upside down so the rotation gives you spin gravity like an O'Neil cylinder, I don't see the point. The gravity is too low. I guess you gain 'free' radiation shielding but I imagine we'd be able to make better shielding by the time we're thinking about colonizing asteroids.


----------



## Swank (Jul 24, 2022)

MaxRelaxman said:


> I was thinking about this, except more culturally recently. Ethnically people would just blend because they live closer together. There's only so much room, even on an O'Neil cylinder. Like other people have mentioned I don't think you'd see physiological differences unless people are living on different planets. So Martians would be taller than Earthers, but shorter than Lunies.
> One thing I think is different from the Expanse is that I don't see people living on asteroids, maybe next to them in space stations but unless you're going to change the rotation of an asteroid in live in it upside down so the rotation gives you spin gravity like an O'Neil cylinder, I don't see the point. The gravity is too low. I guess you gain 'free' radiation shielding but I imagine we'd be able to make better shielding by the time we're thinking about colonizing asteroids.


Depends if you are hollowing out the asteroids in the process of mining them. If so, that's free living space. And why not rotate them?


----------



## Bramandin (Jul 24, 2022)

MaxRelaxman said:


> I was thinking about this, except more culturally recently. Ethnically people would just blend because they live closer together.



There was a Reddit thread recently where a white person grew up in a poor black neighborhood and is now having trouble with whether he's "allowed" to speak the dialect that he grew up with just because he's the wrong color.  The whole issue is so complicated that my opinion is in the realm of "I don't care how, just make it stop being a problem."

In space, there will probably be immigrant guidebooks on what is socially acceptable to assimilate and what isn't.  There's really no telling whether cultural appropriation will start to be seen in more neutral terms again with very little off limits.


----------



## Wayne Mack (Jul 24, 2022)

Swank said:


> Depends if you are hollowing out the asteroids in the process of mining them. If so, that's free living space. And why not rotate them?


Given that travel to asteroid required a viable biome, why carry the materials and spend the additional effort to create another? Does it make any sense to carry additional oxygen to pressurize a mining tunnel? To establish an airlock and, perhaps, have to seal the walls to prevent leakage? Why carry extra rockets and fuel to be used to spin the asteroid? If one had extra rockets, why not direct the asteroid back towards Earth, instead? I feel trying to make the asteroid into a habitable abode would incur too much extra cost and lack any real benefit.


----------



## Wayne Mack (Jul 24, 2022)

JunkMonkey said:


> why?


Given that the station would have unrestricted sunlight, squinting of the eyes would be common place. This would be considered the normal appearance and therefore narrow eyes might become a favored trait.


----------



## Wayne Mack (Jul 24, 2022)

Swank said:


> This is wrong on several counts. First, dark skin came before light skin. Light skin was an adaptation Europeans received that probably allowed them generate sufficient vitamin D, despite short winter days and full coverage clothing. This is what the direct ancestors of modern Britons looked like, 10,000 years ago:
> 
> 
> 
> ...


In that case, I assume that there is agreement that skin pigmentation will adapt to light levels. I will also suggest that, in equatorial regions, darker skin pigmentation predominate. This, I feel is sufficient for the hypothesis that, if the equatorial light levels were recreated in a closed environment, then similar skin hues would result.

I suggest that for a viable station, one would optimize for plant growth and UV radiation is extremely beneficial to plants. One would not filter down UV levels for human benefit. Given that adjusting the station in order to recreate seasons would seem to overcomplicate the station design, I would expect it to be geared towards tropical plant life.

I can only speculate what the driving forces behind space station evolution might be. Two off the top of my head are farmer productivity and the lack of attractiveness associated with sunburn and ski cancer. The person who is best adapted to working long hours under the sun would become the more productive farmer (and farming would be a significant need in sustaining a closed colony). Sunburn directly leads to avoidance of physical contact and peeling skin is unattractive. Skin cancers and their aftermath, especially on faces, would also tend to make people less attractive. Is this enough to spur the development of a new ethnicity in a relatively small, closed community? I don't know, but given multiple generations, it feels plausible.


----------



## JunkMonkey (Jul 24, 2022)

Wayne Mack said:


> Given that the station would have unrestricted sunlight, squinting of the eyes would be common place. This would be considered the normal appearance and therefore narrow eyes might become a favored trait.








Lamarckian inheritance?  or are you suggesting that our habitat-dwelling descendents will be too ****ing stupid to put a hat on?

"Hmm, do I fancy the squinty face idiot getting skin cancer or the sensible person wearing a wide brimmed hat with the interesting, readable facial expressions who can see where he's going? I wonder which would be a better father to my children?"


----------



## Wayne Mack (Jul 24, 2022)

JunkMonkey said:


> Lamarckian inheritance?  or are you suggesting that our habitat-dwelling descendents will be too ****ing stupid to put a hat on?
> 
> "Hmm, do I fancy the squinty face idiot getting skin cancer or the sensible person wearing a wide brimmed hat with the interesting, readable facial expressions who can see where he's going? I wonder which would be a better father to my children?"


Consider reflective light and low angle light.  The O'Neill cylinder typically consists of six panels of alternating land mass and window. In the center of a land section, only one-third of the light energy comes from overhead. At the edges, significant light energy is coming straight up. I am not sure that a hat brim would be sufficient to shield one's eyes.


----------



## Swank (Jul 24, 2022)

Wayne Mack said:


> Given that travel to asteroid required a viable biome, why carry the materials and spend the additional effort to create another? Does it make any sense to carry additional oxygen to pressurize a mining tunnel? To establish an airlock and, perhaps, have to seal the walls to prevent leakage? Why carry extra rockets and fuel to be used to spin the asteroid? If one had extra rockets, why not direct the asteroid back towards Earth, instead? I feel trying to make the asteroid into a habitable abode would incur too much extra cost and lack any real benefit.


If there's ice, there's oxygen. 

Would the crew not value more living space and better particle/radiation protection? Wouldn't operations be easier without pressure suits?

If there is mining mass being flung off the asteroid, then its recoil provides all the delta V you need to start spinning.

If you are riding the asteroid back to earth, why not use those rockets to impart spin?

What is "cost" when it comes to projects like these? You think Boeing is paying for this?




Wayne Mack said:


> Given that the station would have unrestricted sunlight, squinting of the eyes would be common place. This would be considered the normal appearance and therefore narrow eyes might become a favored trait.


So, the new theory is that people who are less attractive don't find partners for reproduction? Do you find that only your most attractive friends marry?



Wayne Mack said:


> In that case, I assume that there is agreement that skin pigmentation will adapt to light levels. I will also suggest that, in equatorial regions, darker skin pigmentation predominate. This, I feel is sufficient for the hypothesis that, if the equatorial light levels were recreated in a closed environment, then similar skin hues would result.


Skin color doesn't adapt. Organisms die off if they have severe difficiencies or rampant cancer. Again, have you seen any white people dying off anywhere?



Wayne Mack said:


> Consider reflective light and low angle light.  The O'Neill cylinder typically consists of six panels of alternating land mass and window. In the center of a land section, only one-third of the light energy comes from overhead. At the edges, significant light energy is coming straight up. I am not sure that a hat brim would be sufficient to shield one's eyes.


The other light coming in is starlight. Do you squint at the Milky Way? There is no light diffusion in space - light travels in straight lines. Shadow is total.



I had hopes that this would be a pretty interesting discussion, but most of what we are talking about is remedial science.


----------



## Brian G Turner (Jul 25, 2022)

We're veering so much toward social politics in this thread that it's going to be safer to close it. Obviously, if you're writing about space colonies feel free to use your imagination.


----------

