Contrary to the old adage “opposites attract,” when it comes to finding a mate, it is birds of a feather who flock together. Research has shown strong evidence for assortative mating, which involves the non-random coupling of individuals who match one another on one or more characteristics (Buss, 1984; Watson, Beer, & McDade-Montez, 2013).
The mechanisms by which this happens are less clear. Watson et al. (2013) present several possibilities. The first is convergence, in which the individuals within the couple will become more similar over time as a result of being together. The second possibility is that the similarity arises from social homogamy, in which those who are more likely to meet are typically located near one another. This usually leads to couples in which the individuals have similar social environments, social backgrounds, and socioeconomic statuses. The third possibility is that market value plays a role. According to this belief, there are certain traits that we value in society, and those who possess these traits have a competitive edge in securing a mate. These more competitive mates will likely choose a partner who possesses a similar level of that trait or characteristic. Finally, active assortment suggests that people will consciously choose to mate with someone who is like them on a particular characteristic.
The likes-attract hypothesis may also explain how similarity within couples arises. Based on the likes-attract hypothesis, individuals relate self-perception on one trait to the selection of that same trait in a potential partner (Buston & Emlen, 2003). Therefore, when selecting a mate, we would show a preference for individuals with traits similar to our own. Those who are well endowed in a particular trait will also be likely to make strong demands for the same trait in the opposite sex.
In a study, Buston and Emlen (2003) examined this hypothesis in relation to the potentials-attract hypothesis to see which better explained our mate choice. Before, getting into their study, it is important to understand the hypotheses that drove their research.
The first is the potentials-attract hypothesis, in which individuals prefer partners with reproductive potential similar to their own. Essentially, a person who has a sex-specific trait that indicates high reproductive value for their particular sex will make strong demands for a trait signaling reproductive value in his or her partner. For example, a woman with clear skin and rosy cheeks, which are signs of health and fertility, would seek a man who is ambitious and wealthy, an indication that he would be a good provider. The potentials-attract hypothesis describes a situation in which traits are measured in terms of their overall reproductive potential.
On the other hand, the likes-attract hypothesis says that individuals will relate their self-perception on a specific trait to that particular trait in a potential mate (Buston & Emlen, 2003). In this case, evaluations are made on a trait-by-trait basis. An example of this would be an athletic and fit woman being likely to seek out an athletic and fit partner.
Buston and Emlen (2003) gave questionnaires to 978 participants, between the ages of 18 and 24, to determine if self-perception was related to the attributes participants valued when choosing mates. All participants were given a mate-preference survey in which they ranked 10 attributes when choosing a partner, and were also instructed to rate themselves for those same 10 attributes (which constituted the self-perception survey).
Results demonstrated that the overall mate-preference score was significantly positively related to the overall self-perception score. Based on the two aforementioned hypotheses, it appears as if the likes-attract hypothesis better supported the data that was collected.
This finding is important, because it explains why so many people end up in homogamous marriages, in which the partners resemble one another on several attributes. In addition, it shows how beliefs about the self can influence our impressions and evaluations of others.
Buston and Emlen (2003) discuss the far-reaching implications of this study. For example, counselors may need to help people in their assessments of both themselves and others. In addition, people searching for mates should be encouraged to look for those similar to themselves, as this may lead to relationships that are both satisfying and stable.
Buss, D. M. (1984). Marital assortment for personality dispositions: Assessment with three different data sources. Behavior Genetics, 14, 111–123.
Buston, P. M., & Emlen, S. T. (2003). Cognitive processes underlying human mate choice: The relationship between self-perception and mate preference in Western society. Proceedings of the National Academy of Sciences, 100, 8805-8810.
Watson, D., Beer, A., & McDade‐Montez, E. (2014). The role of active assortment in spousal similarity. Journal of Personality, 82(2), 116-129. doi:10.1111/jopy.12039