Occasionally I run across the argument, “It’s better to have men as soldiers than women, because a man can sire a lot more babies than a woman can bear. If you have a war and kill off 90% of your young men, you can still get a full crop of babies for the next generation, but if you kill off 90% of your young women, you lose 90% of your next generation.”
I find this line of reasoning rather unsatisfying.
Ignoring the minor fact that if the war’s on your home turf, you could end up with lots of your young women dead whether they’re soldiers or civilians…. From a strictly biological viewpoint, the argument is true. One man + ten women = ten babies; ten men + one woman = one baby.
Now, in a society where the ideal is monogamy, tell me how we’re going to get that one man to sire babies on ten different women without a major breakdown in family and social networks.
Heck, we already know what that looks like. I’m reminded of a bit from Turner and Ehlers’s Sugar’s Life in the Hood where one of them points out that in the community where Turner lives, there is a high women:men ratio (5-10 women to one man; can’t remember the exact number), due to many men being in prison or otherwise unavailable as mates. The result, in that co-author’s opinion, is that a man in that community has no incentive to be a “good” man — really financially support his family beyond the occasional $50 supplement, be present for his kids, stay off booze and drugs, be faithful to his partner — because if his current woman doesn’t like his behavior, there’s someone else who’ll put up with it for the sake of having a man in her life and for the small financial benefit. And so you have the vicious cycle continuing: boys grow up thinking that’s the way to be a man; girls grow up thinking that they can’t expect men to act like adults.
So if you kill off 90% of your young men, either:
- the ideal of the lifelong monogamous marriage goes kerflop, along with all the social structures based on that ideal; you may have a fully populated next generation, but you’ve lost important parts of your society and culture,
- or you keep the ideal, you end up with a lot of unmarried women (cf. late 19th century U.S.)…and your next generation is still small, because 90% of the women aren’t reproducing. You might as well have let the women enlist alongside the men.
(Hmm. I really need to go track down some social histories of the UK and Europe after WWI. Certainly those countries lost large numbers of young men in the trenches, and I don’t have a clue what happened to the population in the following years.)