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Have you ever thought about how people choose their romantic partners? Science indicates that many individuals feel comfortable choosing mates on their own, and have confidence in their choices. But others are less confident and often engage in what’s known as non-independent mate choice, using others' mate choices as standards for whom to seek out and select as mates themselves.
We see this play out all the time: You think your friend’s partner is great, and they have the added seal of approval of your friend, someone you hold in high regard. So you seek out a partner with similar characteristics. That’s called mate copying, and it’s a positive form of non-independent mate choice. (See Street, Morgan Thornton, Brown, LaLand, & Cross 2018; Zhuang, Ji, Zhao, Fan, & Li, 2017; Rodeheffer, Proffitt Leyva, & Hill, 2016; Place, Todd, Penke, & Asendorpf, 2010; Waynforth, 2007.)
Or maybe you’re already in a relationship, but something changes that prompts you to end it and start a new one. For example, due to a decrease in your partner’s mate value, or an increase in your own, you might seek a more attractive mate, someone with characteristics similar to those of your friend’s partner.
Both mate copying and mate switching are positive forms of non-independent mate choice that can be considered adaptive behaviors. They allow you to secure a mate with better characteristics (i.e. healthy, fit, fertile, etc.) than you might have chosen on your own. Plus, mate switching could allow you to go from a bad or dissatisfying relationship to a better relationship than you would opt for on your own.
But there are also negative forms of non-independent mate choice — specifically, mate poaching, when someone steals a romantic partner from another person. Both sexes are guilty of this behavior, but it’s more common among men. Sometimes mate poaching is done for short-term mating (i.e., extramarital affairs), while on other occasions, it's geared toward securing a long-term partner.
Mate poachers have to be deceptive because they can face retaliation in the form of violence from the spouse/partner of the person whom they poach, and they can face reputational damage from being labeled a home-wrecker. Individuals who engage in this behavior describe themselves as mean, unreliable, adulterous, and erotophilic.
A deceptive strategy that works quite well for mate poachers involves becoming friends with the person whom they want to poach (Mogilski & Wade, 2013). Friendship allows for an emotional connection with the intended partner, showing a sense of commitment that eventually helps with mate retention (Wade, 2012; Wade, Auer & Roth, 2009). Basically, the mate poacher becomes a friend, and then when a problem occurs in the intended target’s relationship, the friend is there to help them deal with it — and step in as a new mate.
Mate poaching can be an adaptive strategy, in that it can lead to the acquisition of a new partner (Schmitt & Buss, 2001; Moran & Wade, 2017). But here’s the thing: Relationships born of mate poaching are fraught with dysfunction, including lower commitment, lower satisfaction, lower investment, and higher levels of infidelity (see Foster, Jonason, Shrira, Campbell, Shiverdecker&Varner, 2014).
If you’re going to get help with choosing a mate from your friends, best to find your own candidates with the traits you trust, rather than stealing a friend's partner outright — even if you’re willing to sacrifice that friendship.
References
Buss, D. M., Goetz, C., Duntley, J. D., Asao, K., & Conroy-Beam, D. (2017). The mate switching hypothesis. Personality and Individual Differences, 104, 143-149.
Davies, A. P., Shackelford, T. K., & Hass, R. G. (2007). When a “poach” is not a poach: Re-defining human mate poaching and re-estimating its frequency. Archives of Sexual Behavior, 36(5), 702-716.
Foster, J. D., Jonason, P. K., Shrira, I., Campbell, W. K., Shiverdecker, L. K., & Varner, S. C. (2014). What do you get when you make somebody else’s partner your own? An analysis of relationships formed via mate poaching. Journal of Research in Personality, 52, 78-90.
Mogilski, J. K., & Wade, T. J. (2013). Friendship as a relationship infiltration tactic during human mate poaching. Evolutionary Psychology, 11(4), 926-943.
Moran, J. & Wade, T. J. (2017). Sex and the perceived effectiveness of short-term mate poaching acts in college students. Human Ethology Bulletin, 32(3), 109-128.
Place, S. S., Todd, P. M., Penke, L., & Asendorpf, J. B. (2010). Humans show mate copying after observing real mate choices. Evolution and Human Behavior, 31(5), 320-325.
Rodeheffer, C. D., Leyva, R. P. P., & Hill, S. E. (2016). Attractive female romantic partners provide a proxy for unobservable male qualities: The when and why behind human female mate choice copying. Evolutionary Psychology, 14, 1-8.
Schmitt, D. P. (2004). Patterns and universals of mate poaching across 53 nations: the effects of sex, culture, and personality on romantically attracting another person's partner. Journal of Personality and Social Psychology, 86(4), 560-584.
Schmitt, D. P., & Buss, D. M. (2001). Human mate poaching: Tactics and temptations for infiltrating existing mateships. Journal of Personality and Social Psychology, 80(6), 894.
Street, S. E., Morgan, T. J. H., Thornton, A., Brown, G. R., Laland, K. N., & Cross, C. P. Human mate-choice copying is domain-general social learning. Scientific Reports, 8, 1715.
Waynforth, D. (2007). Mate choice copying in humans. Human Nature, 18(3), 264-271.
Zhuang, J. Y., Ji, X., Zhao, Z., Fan, M., & Li, N. P. (2017). The neural basis of human female mate copying: an empathy-based social learning process. Evolution and Human Behavior, 38(6), 779-788.
