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

[Swank]

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]

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]

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]

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]

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]

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]

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]

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.

"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]

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]

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]

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]

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]

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]

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]

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]

This also might affect eye shape.

why?

 

[Bramandin]

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]

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]

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]

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.