The Setting

Imagine a generation ship of 10-20 generations (200-400 year trip). The generation ship is divided into living crew and frozen eggs.

Upon reaching the destination & for genetic diversity, the crew must begin gestating these eggs and producing colonists.

Meanwhile the crew will continue to produce some of their own children.

The Conflict

People tend to treat their biological children better than adopted children on this ship (not sure if that also applies to in vitro fertilization [IVF]).

From the crew's perspective they and their ancestors did all the "hard work". They and their society successfully completed this multigeneration voyage and risked extinction as they hacked a life out of their new world.

They may wish to ensure their successful society runs things at the new colony.

Since colonists were raised from birth at the colony, other than possible education, there's no real way for them to know that their society could run along any different lines.

The Question

Would this encourage a caste system (ala Larry Niven's A Gift from Earth) in which the crew set themselves up as the "nobility" of the new colony?

Bonus points for answering the following:

  1. Would/could such a stratification be beneficial?
  2. How long might such a situation persist?
  • $\begingroup$ It just occured to me that mandatory slave breeding would need a huge social engineering. Almost no woman from a modern civilisation would accept it . Does your ship have a technology akin to Lois McMaster Bujold Uterine Replicator that would allow this kind of detachment ? $\endgroup$
    – MakorDal
    Commented Jan 22, 2016 at 9:41
  • $\begingroup$ "People tend to treat their biological children better than adopted children on this ship" Is that a statement you're making specifically about this ship or an assumption you're making about humanity in general? It looks like you mean the former but I just want to confirm. $\endgroup$ Commented Jan 22, 2016 at 10:06
  • $\begingroup$ I meant for that to be a generic statement, not just one that applies to this ship. $\endgroup$
    – Jim2B
    Commented Jan 22, 2016 at 13:42
  • 2
    $\begingroup$ I have two daughters. One "biological" and one "adopted". I have two daughters. $\endgroup$ Commented Jun 2, 2016 at 14:53
  • $\begingroup$ en.wikipedia.org/wiki/Anecdotal_evidence - your experience doesn't (necessarily) represent typical behaviors. The en.wikipedia.org/wiki/Cinderella_effect is very real. However, I should not have used the term "adopted". It is step children who suffer higher levels of abuse than biological or adopted children. $\endgroup$
    – Jim2B
    Commented Jun 6, 2016 at 20:39

5 Answers 5


Would such a setup encourage castes ? Depending on the crew culture of origin... Maybe.

Westerner culture always had a semi-fluid system where the best and brightest could climb the social ladder, at least through several generations.

Easterner cultures were more rigid.

Then you have the will, knowledge, and loyalty of the crew to a distant mission and origin. The more ambitious, with knowledge of caste system could implement one. People who would want the best for their children might create a kind of meritocracy where their child get a huge head start, but where the best of the in-vitro colonists (the "tubbies") could still rise

When first writing this, I overlooked an important point : even with IFV, the colonists will be the sons and daughter of the crew, unless they have a mean of breeding the kids without woman bearing them.
If they have this technology, then they can engineer any kind of society they want and the question is very valid.
If they don't have this technology, then many women of age will have to turn into baby-making factory. At this point, either you already have a caste of breaderess on board the ship and you can go for it, or you need to have modified your culture so that women don't care for the well being of IFV children or, finally, you can have modified the society so that most child are raised collectively with a few being raised by families.

The most likely case would be that, over generations, the people (particularly the women) of the ship have become disgusted with the idea of mandatory IFV pregnancy. This would justify the difference of treatment in the children with "naturals" being seeing as for more lovable than "tubbies". And then you have your two-caste society with loved children cared for, and unloved small sized slaves whose care is considered a punishment.

Would/could such a stratification be beneficial?

  • The meritocracy ensure that the colony will get people actively try to better themselves and the settlement.
  • The caste system are quite stable, just or not. Stability is an important success factor for a colony far from it's home.

How long might such a situation persist?
An unbalanced meritocracy is doomed over time as some tubbies will rebel. Give it a few generations. Maybe a century. This one has more chance to evolve instead of degenerating into a civil war.

A caste system is prone to stagnation and could last until it collapsed. As expansion is critical to a budging colony, I'd give them maybe two centuries (8-10 generations) before things go sufficiently sour to get to a radical, violent change. This one has more risks to need a civil war before it can change.

  • $\begingroup$ Thanks for the edit : it's somewhat hard to write here from a smartphone. $\endgroup$
    – MakorDal
    Commented Jan 22, 2016 at 8:20
  • $\begingroup$ Maybe, maybe not - Looking at the history of earth, caste systems have been consistently stable when the people think it is the will of the gods; they only rebel, when the slaves believe they deserve equal rights. What you have here, gives justification to the not-equal belief, and it might be enough for the slaves to internalize it. $\endgroup$
    – Benubird
    Commented Sep 6, 2016 at 21:55
  • $\begingroup$ @Benubird You are right, but sooner or later people will start to rock the boat, maybe even those from the upper caste. That's why I'm giving 8-10 generations before the troubles hit the fan. I'm basing this on an advanced society where some people choose to implement a caste system to protect their kids interests, not a society already divided into castes. $\endgroup$
    – MakorDal
    Commented Sep 7, 2016 at 8:58

It could have this result but it doesn't necessarily would have this result. You can justify it either way, depending on your story.

  • Say the colony is run along capitalist lines, but every adult has the right to claim a large plot of public land for development. As it happens, the adults at the time of the landing all claimed plots next to each other, in a good place for a capital city (good climate, good transportation, ...). The first hospital, the first university are built there. That makes the initial crew richer than the rest. What is worth more -- a square mile in Manhattan or a square mile in Montana? This could last a long time if the wealth of rich people is self-reinforcing.
  • Or the colony does not make the transition away from the shipboard command structure. The captain remains in command until an unspecified time in the future when "the colony is mature enough." Even if promotion to the officer corps is strictly on merit, those raised by officer families would learn how an officer and gentlemen is expected to behave, and hence pass the examination unless they're really stupid. Meanwhile, colonist-born children would have to be really good to overcome that lack of examples.
  • Or the crew has suffered a high degree of genetic damage due to exposure to radiation and a bit of inbreeding, while the colonists are all carefully selected for health. The descendants of the crew become an underclass.
  • Or the crew find that their skills and work culture which where fine on a ship are simply not applicable to the planet. They and the children they raise become an underclass, not a nobility, while they struggle to fit in.

I'd go with yes.

Generation ships are by their nature designed to be remain within the same operational parameters for the entire mission with some safety margin added. So effective generation system should be as static as possible for the designer to achieve.

There are workarounds. I recently asked about a bubble-ring model of generation ship that would get around this by having enough redundancy that some social experimentation at a ring level would be practical. But that requires on entirely different model for how you are using the generation ships so it doesn't apply to your question.

An optimally static society would have no real need for social mobility. People would be tested for aptitude and then trained for tasks that suit them best.

Since the crew would be chosen for high ability at their tasks and high ability needs to be available for the following generations as well, it is reasonable to assume the original crew was chosen for high natural aptitude at their specific tasks. The eggs would presumably also be as much as possible be chosen for natural aptitude since that is all that can be done on Earth.

Since the crew was chosen for aptitude at specialized tasks and children socially take after their parents and the ship would be too static, unless something goes catastrophically wrong, to need social mobility it is reasonable to think the crew positions would be nearly hereditary. Specifically there would be division between leadership, management and technical positions. Something resembling the officers, NCOs, and the crew division of military systems. If it works and all that.

Once landfall is made the need for static society would not really change. You'd simply have vastly increased need for management and technical positions. Thus leadership positions would remain in the hands of the ship officers and the eggs would have been chosen for aptitude at the management and technical positions and be used to rapidly increase those classes of people. This would create a need to rapidly educate and train large numbers of people which would continue the ship tradition of training people to specific positions based on aptitude.

So the castes would probably be largely hereditary initially with some limited mobility to account for the fact that even with genetics and upbringing people are probably not that predetermined. But the division would not be between the crew and colonists rather it would be a continuation of the rigid social system on the ship into which the new born would be raised into.

Two notes though:

First, such a caste system would actually be fairly good for the needs of the initial colonization. Democracy and freedom are required for efficiently deciding what to do. When you have an abundance of things to do with limited resources and probably a fairly specific plans on how to do them, a society with strict hierarchy works just fine. So the caste system might actually be an advantage, not something to avoid.

Second, as the demands of the society change, the social structure will automatically evolve to match the needs. There will be friction, but generally you can assume that once the caste system is not useful, ie the amount of resources grows so there is some need to think about the direction of the colony not just survival, the society will move on. And unlike aristocrats of our own world, the crew would have access to information telling them about the inevitability of social evolution. They'd probably even have plans drawn by some very smart people back on Earth about how to handle the transitions to more liberal society.

  • 1
    $\begingroup$ You overlooked the fact that colonists are primarily born out of in vitro, mandatory fecondation, once the ship has arrived. $\endgroup$
    – MakorDal
    Commented Jan 22, 2016 at 9:38
  • $\begingroup$ @MakorDal I did. Thanks. Although not sure it makes any change. The selection criteria would still be different and the same social distinctions would still apply. Biggest difference would probably be that since there would be no time for the distinction to settle in before landing, the society would be less conservative and there would be less chance of issues once transition away from hierarchical society becomes necessary? I'll think about a proper edit. $\endgroup$ Commented Jan 22, 2016 at 9:53
  • $\begingroup$ Actually edited out the answer while trying to fix the error, will re-edit... $\endgroup$ Commented Jan 22, 2016 at 10:15
  • $\begingroup$ I also had to violently edit my own answer to take my own comment correctly into account. $\endgroup$
    – MakorDal
    Commented Jan 22, 2016 at 10:33
  • $\begingroup$ @MakorDal Thanks again for pointing out the error. Turns out that while the difference doesn't change the "shape" of the answer it did require an almost complete rewrite since all the details do change. So just "removing the error" also removed the actual answer. As rewritten I think the answer actually does a better job of explaining what I meant. Although edits tend to make a mess of the logic.. $\endgroup$ Commented Jan 22, 2016 at 10:34

While a neo feudal system is possible under this construct, several other variations may also arise:

Plutocracy/oligarchy. The crew, having access to all the ships systems and resources, can control virtually every aspect of the new colonists lives. This can be in the form of soft control (i.e. filtering information) rather than hard repressive control. The Crew and eventually the descendants of the crew will be much like "old money" and be able to subtly guide development in ways which allow them to retain control.

Hydraulic Empire. Since the crew controls all aspects of the ship's life support systems, they have 100% control over the lives of everyone aboard. All acts and decisions have to flow through them, and a hereditary caste of "priests" and God Emperors may arise to control the life support system(s) of the ship and any subsequent colonies in the system. I include artificial colonies built in asteroids and on airless moons, and terraforming projects which require the special skills of the "priesthood" to manage.

The downside of this is the "three generation rule", (from shirtsleeves to shirtsleeves in three generations), which suggests the various aristocrats/plutocrats or hydraulic empire priesthoods will become corrupt and ineffectual in the third generation after they are established. Most systems on Earth avoid that particular fate because they are very large and usually not tightly bounded (there are always ways to ensure some forms of social mobility and allow truly talented people into the upper echelons), but an interstellar colony is a closed system and has too few people in the initial generations to ensure that there will be enough social mobility to keep the system open and viable, regardless of the social and political systems developed when the ship arrived.


I'd go with yes.

I feel this would also start in the ship portion of the trip as well. Crew members such as the Captain and those who perform essential duties will see themselves as more important than the others. The ship's ecosystem works in favor of these essential crew and this favoritism would be the cause for a split between crew.

Ascension gives a good representation of what might happen on a generational ship and answers "yes" to your primary question. The whole series was on Netflix at one point.


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