Source: Matthew Thorn/Flickr

How do parents influence their children’s choice of partner?

I’m not talking about direct influences, here. It’s certainly true that in some cultures parents arrange marriages for their offspring, and even in the most liberal societies it is common for parents to pass judgement on the boyfriends and girlfriends their kids bring home for dinner. But what about more subtle influences that neither parents nor offspring are likely to be aware of?

You may have heard of imprinting. It’s the biological phenomenon that explains why ducklings follow the first individual they encounter after hatching. In normal circumstances, that makes sense because the chicks are likely to spot their mother first. Many psychologists think that humans also imprint on their parents, and that this imprinting affects the type of person we find most attractive later in life.

Past research has shown that heterosexual men and women have a ‘type’ when it comes to hair and eye color, and that the type matches their opposite parent. Of course, many of us have the same hair and eye color as our parents, which is why it’s important to test whether we prefer partners who look more like us or more like our parent: the parents win out.

We also know that women who grow up with an older father tend to prefer older men themselves.

Zuzana Štěrbová of Charles University in Prague, along with her research collaborators in Prague and São Paulo, decided to investigate whether other physical qualities of our parents can influence our mate preferences. They recruited around 900 people who were attracted to men: ~750 straight women and ~150 gay men.

Each of the volunteers was shown a 5x5 grid of images. Each image was a silhouette of a naked man. The volunteers’ task: to pick out the man whose body looked most like their own (if they were male), most like their ideal partner, most like their current or most recent partner, and most like their father as they remembered him from their .

But the images weren’t chosen randomly. They were taken from a 1950s textbook — The Atlas of Men — which depicts a variety of men’s bodies according to their somatotype. A male body’s somatotype can vary from ectomorphic, to endomorphic, to mesomorphic. In simpler language, a man can be skinny, fat, muscled or any point in between.

Štěrbová found that gay men and straight women didn’t vary in their preferences for men’s bodies. Both men and women preferred a man who was somewhat midway between muscled and skinny, and didn’t prefer a man who was fat. When it came to actual partners, gay men and straight women were different. First of all, there was a lot more variation in the bodies of actual partners than ideal partners. Gay men’s partners tended to be fatter (or, at least, to be perceived as fatter by the volunteers themselves), and straight women’s partners tended to be more muscled.

What about the fathers’ body types? The researchers found that straight women’s ideal partner body shape was similar to the body shape of their fathers. The effect was weak, but present in all three components: endomorphy, ectomorphy, and mesomorphy. Gay men’s ideal partners and their fathers were only similarly skinny.

However, these preferences did not seem to translate into the real-world choice of partners, because the volunteers reported that the bodies of their fathers and their actual partners were neither similar nor dissimilar. This could be because we are constrained in our ability to choose our partners: we may have to compromise because our preferred partner doesn’t prefer us, we may value other traits more highly than body shape and so choose a partner based more on those instead, or we may have a limited pool of partners to choose from.

In an important further analysis, the researchers showed that women who reported a good childhood relationship with their father were more likely to express a preference for male bodies that were similar to their fathers’. This makes sense if we think of imprinting as a way of modeling our parents’ choice of partner. In other words, maybe women unconsciously perceive their fathers as a good example of an ideal partner. But, if true, it is unclear why there was no such link between the quality of father-child relationship and mate preference in gay men. As the researchers point out, it could be because gay men and lesbians tend to report lower quality relationships with their parents, and it is plausible that for the imprinting-like effect to fully emerge it is necessary that parents and children have a good relationship.