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Study skewers long-held theory that 'opposites attract'

Roz Brown

(New Mexico News Connection) The age-old theory that opposites attract has been debunked. According to analysis of more than 130 traits in a study that included millions of couples over more than a century, the authors found that partners are more likely to be similar than wildly different. 

Tanya Horwitz, a doctoral student at the University of Colorado, said 82 to 89 percent of traits analyzed - ranging from political leanings to substance-use habits - revealed people tend to find partners with similar habits.


"People meet the people they get into relationships with often within social networks," she said. "So, if a person spends a lot of time in bars or taking substances, they are probably also going to meet a lot of other people who have similar substance-use patterns."

Horwitz added the analysis shows individuals tend to partner with those who are different for only three-percent or less of the traits studied. Meanwhile, traits like height and weight, medical conditions and personality showed far lower - but still positive - correlations. The study did not include same-sex couples because their patterns may differ significantly, which the authors are now exploring separately.

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While the study showed partner resemblance was far more similar than dissimilar, Horwitz noted sleep patterns were a surprising outlier. 

"We're looking at tens of thousands of couples, so it was a large sample," she explained. "But we did find that if you're a morning person, you are slightly more likely, in the sample, to be in a long-term relationship with a night owl - and we kind-of don't know why we found this."

She said the study involved two methods - a meta-analysis looked at 22 traits across 199 studies, including millions of male-female co-parents, and engaged, married or cohabitating pairs. It also includes analysis of 133 traits across almost 80,000 opposite-sex pairs in the United Kingdom.