Hrm... interesting. Reading that, however, doesn't seem to imply that a small imbalance in the sex ratio necessarily makes anything more than a small difference. Did I miss it, or is there something in the original actual paper that implies small imbalances produce large effects? (My investigation into this topic is practically nonexistent, however.)
(I am curious also about the wording... Sexually active males vs sexually receptive females.)
If you look at the study (warning: PDF) you can get quantified information. Looking at page 5 you can see that a woman in .925 city (like Philadelphia) will get married a year earlier than in a 1.075 city (like Portland). So maybe the effect isn't that big after all.
Although I would expect the results would be more dramatic if we comparing the operational sex ratios of countries rather than cities. If the sexual market is unfavorable, it's a lot easier to import a mate from another city than another country.
A thought occurred to me today as I skimmed an article in a rationality forum where the subject of gay marriage cropped up; seeing as the issue has been hotly contested in various public fora and especially the courts, what about poly? After all, many if not all the arguments for gay marriage apply to poly marriage as well.
Questions for LWers who are currently in a such a relationship, or have an opinion to share:
Do polies want to marry each other or do such relationships not lend themselves to permanence above a threshold of partners? Should polies campaign for the right for a civil union anyway? what are the up and down sides of this? etc