Aug. 27, 2010 -- It just seems so, but it isn't: Husbands and wives don't become more alike over time.
That's according to a study published in the August issue of the Personality and Individual Differences.
Rather than becoming more alike over time, people simply tend to pick mates based on shared personality traits, study researcher Mikhila N. Humbad of MSU tells WebMD.
Researchers at Michigan State University analyzed data from the Minnesota Center for Twin and Family Research on husbands and wives in 1,296 married couples. They wanted to determine whether men and women become more similar as time passes after the initial honeymoon glow grows dim.
They analyzed personality characteristics, such as positivity, negativity, optimism, ambition, aggression, and how people handle stress.
Similarities From the Start
"Existing research shows that spouses are more similar than random people," Humbad, a doctoral student at Michigan State, says in a news release. "This could reflect spouses' influence on each other over time, or this could be what attracted them to each other in the first place."
The researchers say that husbands and wives followed over time did not become more alike with more years of marriage. So contrary to popular belief, it's really similarities in the beginning that are most important in lasting marriages, the researchers say.
Aggression seems to be an exception, the researchers say. That makes sense, Humbad says, because "if one person is violent, the other person may respond in a similar fashion and thus become more aggressive over time."
The researchers say their findings could have implications for future spouses, as well as for their children.
"Marrying someone who's similar to you may increase the likelihood that you'll pass those traits on to your children," Humbad says.
She notes that the findings come amid a backdrop of a booming matchmaking industry in which many companies claim they can match people based on similar characteristics.
"I'm not familiar with how those do the matching," she tells WebMD. "But according to the paper I wrote, married couples are already choosing each other based on traits. I could see how matchmaking firms use that to their advantage. I think they are already doing that, finding people with certain traits."
Humbad tells WebMD she is working on a dissertation she hopes will shed more light on the subject. "Specifically, I'm doing a study that uses a speed-dating design, where I have five males and five females who don't know each other and are single interact with one another for five minutes each," she tells WebMD. "Based off of this five-minute conversation, I want to see what their preferences are in terms of who they would select as a dating partner, a long-term partner, who they are most attracted to."
She says she hopes in the future to be able "to figure out the process of how we select our spouses a bit more."