Why we're more likely to date someone who has an ex

Most people would agree choosing “the right” partner is fairly important, and a bad selection in this area can be devastating. Most people want to attract a partner, and this involves a combination of self-promotion, and taking down the competition in order to appear to be “the right” partner. Some of our efforts are conscious and some are unconscious.

Research has found people with relationship experience, all else being equal, tend to be more romantically desirable than people without relationship experience. In other words, people are attracted to others who have already been “pre-selected” (or pre-approved). We call this phenomenon “mate copying”.

Mate copying can be thought of as purchasing a product (a romantic partner) after seeing others (former partners) “use” it. By virtue of having been in a relationship, an individual is communicating they have “desirable” romantic characteristics (these have appealed to at least one person previously) and you can be confident there is something about them that is appealing.

Do men and women mate copy?

In a sense the previous partners of a person are “endorsing” them, or attesting to their romantic competence. By doing so, they are indirectly offering relevant information about the person.

But why might this be useful? Well, if you are going to make an important decision (who to partner) you generally want a fair bit of relevant information. Knowing someone else has been chosen before is additional relevant information that will help you make your decision.

But there is a sex-difference here, and it essentially comes down to biology. There is plenty of literature supporting the idea men are largely attracted by physical qualities (physical beauty, youthfulness).

Women, however, are generally attracted to less observable characteristics (social dominance, kindness). Where men can get a fair bit of mate-relevant information from simple observation of a potential partner, women can’t, and are encouraged to look for additional information. One cheap source is knowing what other women think of a man, specifically, whether or not he is considered a good romantic prospect.

While some researchers have found evidence of mate copying in men, there is a fair bit of literature suggesting the phenomenon is quite a bit stronger among women.

One reason for this is men don’t get as much out of mate copying as women do. The information gains men achieve by knowing what other men think about a woman are marginal.

Being in a relationship is attractive … or is it?

Although you may not have heard of “mate copying”, you may have heard of “the wedding ring effect”. This broadly describes the popular(ish) belief that wearing a wedding ring makes a man desirable, because he has obviously won the romantic favour of at least one opposite-sex person (his wife), and he is willing to commit.

Given indicating a willingness to commit makes a man very attractive, and considering he is conveying a lot of positive characteristics (he’s likely a good partner, he’s willing to commit), the persistence of this belief is not surprising.

However, evidence doesn’t support the idea married men are more desirable than single men. A big reason for this is married individuals are so much harder to attract and/or date than single individuals. Also, there are some strong moral proscriptions against pursuing a married person.

It’s not all about quantity

One of the interesting things about mate copying is that, like with many things, quality is more important than quantity. It’s known a man is much more desirable if his female partner (current or former) is highly attractive (than if she is less attractive). But we also know that while a moderate amount of relationship experience makes a man more desirable than if he has none, too much makes him really undesirable.

A study I co-authored looked at how romantically desirable a man was perceived to be, as a function of how many partners he’d had in the past four years. Men with one or two previous partners were far more desirable than men with none, but men with five were far less desirable than any of these.

This non-linear relationship might seem curious – if a bit of relationship experience is desirable, wouldn’t a lot of experience be really desirable? Well, no, and the reason probably has something to do with promiscuity.

While having had five or more previous partners is certainly far from unheard of, it may indicate the person can’t or won’t maintain a relationship for long. Maybe they have trouble committing, or maybe they are more interested in quantity. Whatever the case, they are indicating undesirable relationship qualities.

Mate copying among nonhumans has received a lot of attention in the past several decades, with numerous authors finding evidence for it in aquatic, avian and terrestrial animals. While enquiry into the existence of the phenomenon among humans began far more recently, preliminary evidence suggests it definitely exists and is an extremely powerful attraction force.