More than half the American population is single and ready to mingle, while the other half is presumably in harmonious relationships laced with sugar, spice, and everything nice (or so we believe when we get lonely). When you eye someone across the room, they could be single or taken, but do we really care? According to a recent study published in the Journal of Research in Personality, people who steal partners are more likely to have bad relationships and commit infidelity.

"People who are poached, on average, were willing and desirous of sex outside committed relationships," Josh Foster, lead author of the study and associate professor of psychology at the University of South Alabama, told The Huffington Post.

The researchers define “poaching” as one partner successfully coaxing the other to end a relationship to begin one with them. It seems practical that people who are poached by their partners show less commitment and satisfaction in their existing relationship. This poses the question, if they were willing to abandon a partner in the past, why would they not be willing to do it again?

Foster and his colleagues sought to observe how relationships formed via mate poaching, or stealing someone’s partner, function by conducting a series of three studies at the University of South Alabama. The first study included 84 participants, the second study 138 participants, and the third used a cross-sectional sample of 219 participants. All of the participants across the three studies were heterosexuals involved in romantic relationships.

In the first of their studies, 84 young participants with an average age of 19 were all in romantic relationships. They completed a series of questionnaires once every three weeks for a nine-week period. The participants responded to statements such as, “I feel satisfied with our relationship” and “Our relationship makes me very happy,” on a one-to-eight scale, which ranged from do not agree at all to agree completely, according to PS Mag. The participants were also asked whether they kept an eye out for other potential partners and whether they engaged in any type of flirting.

The findings revealed those who reported being poached from another partner began the study with lower levels of commitment to their current mate. These “functioning differences” grew wider as the study continued, wrote the researchers.

In the last two longitudinal studies, the researchers added explanatory variables, like personality traits, to determine why someone would be more likely or more willing to be poached from their current partner. Foster and his colleagues surveyed 138 participants — over seven percent women with an average age of 20 — four times over the course of nine weeks. This group was in current romantic relationships that had lasted from zero to 36 months.

Men and women who said they were poached by their current partner started the study by reporting less commitment to their current relationship, feeling less satisfied in it, committing more acts of infidelity, and seeking more alternatives. However, unlike the first sample, this group did not show deterioration in their relationship over the course of the study, according to The British Psychological Society. This may be attributed to the study's short duration or because the relationships had already reached their lowest level of deterioration.

The third and final study not only focused on the way the participants’ current relationship formed but also on their personalities and altitudes. This would help the researchers determine out of the 219 participants that were poached which ones would be more likely and more willing to commit infidelity.

Foster and his colleagues wrote: "individuals who were successfully mate poached by their current partners tend[ed] to be socially passive, not particularly nice to others, careless and irresponsible, and narcissistic. They also tend[ed] to desire and engage in sexual behavior outside of the confines of committed relationships."

Narcissism and sociosexual orientation were the most significant predictors behind dysfunctional relationships formed from mate poaching. Partners who were poached were more likely to be narcissistic and laidback about monogamous sex, therefore making them more susceptible to be poached again by someone outside their current relationship.

The phrase “once a cheater, always a cheater” was also found to hold true in a similar study presented at the annual American Psychological Association convention in Washington, D.C. Over 480 unmarried adults between the ages of 18 to 35 were observed to see if people who stray in one relationship are more likely to do so in the next. The findings revealed people who cheat on their partners in one relationship are three-and-a-half times more likely to report cheating again in their next relationship. In addition, the people who were cheated on in the past are also more likely to be cheated on again.

This series of studies also suggests you shouldn't make hasty judgments, Foster highlights one single action should not determine the quality of a person. This trend observed is based on theory and shouldn’t be taken too seriously on a personal level.

"People are much more complicated than one thing that they've done," Foster said.

Perhaps people can really learn from their experiences and mistakes, especially in love. After all, doesn’t everyone deserve the benefit of the doubt? Or innocent until proven guilty?

Sources: Campbell WK, Foster JD, Jonason PK, Shiverdecker LK, Shrira I, Varner SC. 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. 2014.

Knopp K. Once a Cheater … American Psychological Association convention in Washington D.C. 2014.

Published by Medicaldaily.com