The greater evil: genetic engineering vs baby killing? another option?

Question

A generation colony ship (a space ship capable of sustaining enough people to provide enough genetic diversity to prevent inbreeding indefinently) of 10,000 'families', 80,000 people, is set loose from earth orbit into deep space, in order to ensure inbreeding is prevented, one of two courses must be taken; multiple forced pregnancy of all women, until they produced two viable children, one male, one female, and forced abortion of same-gender and disabled (especially mentally- and sexually-disabled, but likely any disablement) fetus's.

That's pretty bleak and brutal... but the only other option is genetic engineering; so this would mean forced genetic sampling of all men and women, bringing the two together in an egg, changing it to remove disablements and manipulating to the "appropriate gender", and likely some women would act as baby-machines for a living, so that pregnancies would not be forced...certainly I wouldn't want a nazi generation colony ship, but this looks like where its heading.

would any woman really be okay with being a baby machine? i know some did similar in ww2 for the nazis, but would they if they had a "better" means of making a living? How many women, given total freedom would get pregnant at all? If its half, they would go through an average four each, given total freedom would they do that and knowing it wasnt their kid?

Or we could go full-on genetic engineering, vat-growing, cloning. hooo boy.

Something on earth is lost here, any suggestions?

Answer 1

You scenario is brutal, unpleasant, unethical and will likely fail. My spike (or steeple) method might work. Generation ships that can accommodate up to 100 people, but typically have 10 to 20. Launch occur several times per year (for many centuries)

Each craft does a shake down cruse about the inner solar system. When the natural leader decides to join a spike of craft all leaving in the same direction, they go until they decide they should return to the inner solar system. The craft are moving both away and toward the sun at a wide variety of speeds and accellerations. It is a two way convoy, very long, but very narrow, the craft can exchange energy and information, by laser beam when they pass each other and rarely people and supplies can change craft. About 0.1 light years from Earth, too much energy will be needed to send data to Earth, but it can be relayed many times in the spike to get the data to Earth. Earth cannot get compliance to their directives except by threatening to stop building generation ships of gradually improving design. Most every one in the spike will die if Earth stops sending out more generation ships.

Inbreeding is best minimised by starting with no men and having only rare boy births. Eventually the sperm banks and embryo banks will fail along with all other systems on the craft, but the rare boys can refill the sperm banks, but inbreeding will be the limiting number of generations, as I don't think even a million humans is enough to avoid gradual deterioration. Gene diversity may be the most limiting aspect of generation ships. You also need to address the declining diversity of the plants and animals on each craft. Neil

Answer 2

You've got too many assumptions, and not enough facts (although this is just a scenario, you need some added factors that would allow the ship to be populated).



What happens to "old people"? The idea would be that breeding would be "replacement only", otherwise, the population would very quickly outgrow the environment. And, with it taking so many years to bring a child up to the level where it can function properly in that environment, you'd probably have extinction long before the second generation got started.

Answer 3

The Polynesians dealt with this exact same problem: small island isolated from other islands ===> small population ====> Inbreeding cannot be avoided. ===> High incidence of birth defects.



Solution: Allow defective children to die. This removes very quickly most defective genes and keeps new defective mutated genes out of the gene pool and the effective birth rate low. There is no need to limit sexual activity, normal attrition (death by natural causes + death of defective children) held the population stable