07/09/2014 05:38 pm ET Updated Sep 08, 2014

Economic Dependence Promotes Prudishness

Stay home, bake white bread, don't sleep around. (Credit: Karen/Flickr.)

Marriage, according to those who habitually preface the word with "traditional," is a collaboration, with complementary roles, filled as predictably by one woman and one man as peanut butter fills the gap between two slices of white bread.

If you encounter somebody clinging to this view of marriage, in which women happily traipse down the church aisle into economic dependence on their menfolk, then I'm sure you can predict their views on sex and the thousand other issues that inhere to sex:

"Sex education? Abstain until marriage, 'cause true love waits."

"The pill? OK if you're using it to control your acne."

"Abortion? Causes all those calamities that the greenies like to pin on climate change."

OK, my clumsy stereotype grows unkind. My point is that, more often than not, women's economic dependence on men is bundled up with strong views against sexual promiscuity.

But why? Are economic dependence and anti-promiscuity morality both symptoms of the same cause? Patriarchy, perhaps? Or does one bring about the other? A new study in Archives of Sexual Behaviour suggests that economic dependence might lead to anti-promiscuity views.

Paternity No Laughing Matter

The neonatal ward isn't the place to crack jokes about paternity. In fact, most people, especially relatives of the new mom, go to great efforts to comment on the newborn's likeness to the guy who thinks he's the dad.

Paternity strikes such a raw nerve with men because they can never be truly sure that they're the father -- at least they couldn't until recent technological developments in DNA analysis made it possible.

And yet throughout our evolutionary past, some men thought they were working hard to raise their own genetic progeny when they were actually rearing the young of another. Men who were suspicious, jealous and not prepared to raise another man's children might not have won any nice-guy prizes, but they did ensure that their hard work contributed to the success of their own genes, including any genes that disposed them to jealousy and vigilance about paternity. Unfortunately, we are all descended from many such men.

Today, humanity's long history of insecurity over paternity can be seen in the politics of paternity testing and the undignified squabble over how many children are really sired by someone other than Dad.

Sensitivities over paternity have shaped religious practices, laws, customs for the inheritance of wealth, and behavioral norms.

In their pop bestseller Sex at Dawn, Christopher Ryan and Cacilda Jethá argued that sexual jealousy and paternity insecurity are newcomers to human society, almost unknown in our species' long hunting-and-gathering past, where love flowed more freely and couples stayed together only briefly. The economic changes wrought by farming tied families to the land, necessitating cultural innovations to ensure that wealth and land stayed within the family.

Ryan and Jethá make several mistakes, including unduly romanticizing our hunter-gatherer ancestors and viewing culture as something separate from biology. The cultural practices that surround fidelity and conception are more usefully viewed as extensions of men's evolved paternity insecurity. And the scale of those extensions varies among places and over time.

When to Worry About Promiscuity

When women depend economically on their husbands or partners, then both women and men should value paternity certainty more highly. Men working hard to raise a family have plenty to lose, in evolutionary terms, if the children they raise are actually sired by somebody else. When men don't do much for their partners or the offspring, they should be much more chilled about paternity, and thus much more relaxed about sexual promiscuity.

Likewise, when a woman depends heavily on a man's labor or the money he brings into the household, then the cost of losing him is much greater. There are two ways that she might lose him through extra-pair sex. If he has other sexual relationships, he could run off with one of the other women, leaving his existing family in the lurch. But when she has extra-pair sex and gets busted, she might lose him -- or worse: Jealousy can trigger psychological abuse and violence.

In the recent paper that inspired this post, psychologists Michael E. Price, Nicholas Pound and Isabel M. Scott, from Brunel University in the UK, sought to test the links between women's economic dependence and both women's and men's attitudes to promiscuity.

From online surveys of more than 5,000 Americans, Price and his colleagues showed that when the women in a subject's social network depend economically on men, then subjects tend to judge promiscuity more harshly. And the effects weren't spurious consequences of religion, ethnicity or political conservatism. When they fitted these other variables into their statistical tests, the association between female economic dependence and opposition to promiscuity remained.

Price also asked whether the association arose as an artifact of geography: On questions of morality and gender roles, Texas and Utah, for example, differ culturally from, say, Massachusetts and California. States in which women earned more were also more relaxed about promiscuity. And this result arose out of the effects that women's earnings had on female economic independence.

Even more compelling, by comparing the attitudes of geographic neighbors in the same or nearby zip codes, Price and his colleagues found that the association held. Irrespective of where you live, the economic dependence of the women in your social network predicts how you feel about promiscuity and non-marital sex.

We've known for some time that variation among societies in sexual morality is associated with variation in gender roles and, especially, earnings. The exciting development is how the new research suggests the patterns emerge from the bottom upward, with individual attitudes being shaped by prevailing economic circumstances in their close social network, at least in part.

I'm interested to know what the authors think about the relevance of their data to Roy Baumeister and Kathleen Vohs' ideas on sexual economics, which hold that women restrict the supply of sex under circumstances when they have the most to gain from a high price. This interpretation is not inconsistent with Price et al.'s arguments about paternity certainty. But high female economic dependence presents exactly the kind of economic situation in which women need to drive a hard bargain in the sexual marketplace. Intriguingly, women took stronger anti-promiscuity stances, on average, than men did.

There are so many studies I would like to see done with a view to teasing out the causal relationships and how attitudes toward promiscuity change in the headwind of religion and other cultural forces. But this finding explains much about some of the trickiest ideological differences both within and among societies.

It could explain how economic changes since World War II paved the way for the sexual revolution, and why conservative politicians, especially in the U.S.A., seem equally hung-up on sexual liberty and the growing proportion of breadwinner moms.

And it may form an important ingredient in the ever-growing and dangerous ideological chasm between patriarchal theocracies and more gender-egalitarian democracies.

Thom Yorke singing Radiohead's "True Love Waits"

P.S. I always relish seeing how other media cover research concerning issues touching on sexual morality. According to Science 2.0's news staff, "If Women Want Their Promiscuity To Be Accepted, They Have To Earn More Money, Say Evolutionary Psychologists". Keith Perry of The Telegraph reckons, "Promiscuous women more likely to be tolerated if they are high earners." And Lydia Smith, writing on International Business Times, got even pithier, declaring, "Only Poor Women Are Branded Sluts."

These were the first three links to news stories that popped up on Google. Not one headline reflects the real message of the study, but they all find a short path to slut shaming. For the record, the study tracked attitudes to women's and men's promiscuity.

Rob Brooks does not work for, consult to, own shares in or receive funding from any company or organization that would benefit from this blog post, and he has no relevant affiliations.

This blog post was originally published on The Conversation. Read the original post here.