What should the ratio of Men:Women be (and minumum number of each) to populate Mars?

Factual Questions
41

Not sure what you mean. The article pretty much bears out what I said - the original Pitcairn/Norfolk population was the Bounty mutineers, who effectively reproduced with their accompanying Polynesian women while ensuring by various means the accompanying Polynesian men could not reproduce. So 11 women, 9 men, and a baby.

Browsing the article linked, it appears to bear out my contention that this narrow gene pool did not produce any significant problems - the article mentions somewhat higher blood pressure and cholesterol issues, but nothing that appears to be colony-limiting, despite growing to several hundred individuals on Norfolk and Pitcairn.

But the trials in the mid-2000’s did reveal the culture of exploiting younger girls, by the adolescent and adult males. That, to me, seems to be a social issue not genetic.

But yes, I think the risks of genetic bottlenecks are overestimated. Perhaps another issue to consider, that the people involved with the Pitcairn situation had a lot more “pre-screening”. The bounty sailors were the survivors of appalling conditions in England which would have weeded out the less fit, then subject to even more tests of health working as sailors. The Polynesian lifestyle was likely only marginally better.

The standard model of human development for millennia was that the children were exposed to a range of diseases, and a significant number died in childhood. The survivors were the ones with the best health and best immune systems. There were also no insulin or glasses or hearing aids or preemie incubators or widespread caesarians or other medical aids to allow survival for people with difficulties. The generation that chooses to go to Mars in a few decades or more will have had progressively more medical tech over the previous over 150 years, to prevent weeding out of the less healthy in their family tree.

As for ratios, cheating, etc. - we assume that this will be like modern, huge anonymous western society. I suspect it will be more like an old-time village, unless we are talking thousands of people. Conditions, at least initially, will be very cramped. Opportunities for hanky-panky would be severely limited. The problem isn’t the cheating, but dealing with consequences. Plus, sexual tension is only one source of conflict. More likely, the issue will be how do you stop spousal abuse, murder, and pent-up anger that deteriorates into blind range and potentially colony-threatening sabotage?

(Even if you paired up everyone, how would you deal with losses like untimely death that would create unpaired colonists?)

While my male point of view makes me chuckle at the idea of “10-to-1” women to men ratios, and it’s good for a few chuckles, practically speaking - a polygamous or polyamorous society will never work long term. The traditional social structure is monogamous pairs (at least for a time). Polygamy only works with serious social power imbalances, and obviously falls apart after the first generation. Humans are designed mentally to pair and bond. both sexes can display extreme jealousy at sharing a partner or the perception, real or imagined, someone else is monopolizing their mate’s affections.

I’m sure the turkey baster and frozen sperm option is pretty good - but has anyone really checked on how long frozen sperm is good for? The first generation at best, I suspect. As for reproduction rates - until recently, 5 to 10 children was not unusual. Plus, once the older children reach about 10 years old, they can effectively also help care for the younger ones, a family role all too common until recently.

42

The kind of childcare economy you’re talking about would be fine for raising agricultural laborers who are expected to contribute nothing more than a strong back and a closed mouth. Then mom can work in the fields 12 hours a day with a nursing infant strapped to her back, the kids older than 10 in the fields as well, and the little kids left on their own to look after each other as best they can.

But are you going to be able to raise skilled engineers and technicians and scientists that way?

Martian colonists aren’t going to be able to follow the social structures of neolithic farmers. They’re going to have to maintain an advanced industrial economy, or die. That means kids have to be intensively trained in esoteric skills like reading and writing and arithmetic from an early age. It means intensive supervision by competent adults, because there’s very little room in the colony for people with strong backs and weak minds. A society where most kids end up with an 8th grade education because they were put to work as laborers in the farms and factories and mines doesn’t strike me as workable on Mars, a planet where if you go outside you’re dead.

43

It’s not really true that they’d be cut off from all re-supply. The big things like habitat modules, yeah, those you really only want to send once and be done with them (or better yet, building them on site). And the humans themselves need to be packaged with a lot of big expensive life support to make the trip. But it wouldn’t be hard at all to send a small parcel with replacement computer chips, new vials of sperm, and so on every decade or so. Heck, we’re already sending new spacecraft to Mars every synodic period (2-3 years), like clockwork.

44

Even if we ignore all limits to growth other than birth rate, the M/F ratio affects only the first generation, followed by exponential growth, so it’ll only affect a constant multiplicative factor in total colony size after the 1st generation, and not steady-state growth rate.

In the long run, the ratio will be about 1:1, so the starting ratio doesn’t really matter much.

(Other than for the male fantasy aspect, that is.)

But the growth rate for the first 15 to 20 years would be dramatically affected, assuming the colonists make optimal use of their “resources.” In that case, a low M/F ratio would be best, provided there are enough men to provide sufficient Y chromosomal diversity. With turkey baster technology and sufficient incentive, what’s the limit of the number of women a man can fertilize in say, two years? Reaching that limit might take a bit of fun out of the fantasy.