The real reason some people end up with partners who are way more attractive

In a study published last year in the journal Psychological Science, researchers offered a fascinating explanation for when and where couples of mixed attractiveness are most likely to arise. The study’s psychologists, from the University of Texas at Austin and Northwestern University, asked 167 heterosexual couples how long they had known each other and whether they were friends before dating, and had a third party rate each persons’ attractiveness. They found that heterosexual couples who were friends before they dated were more likely to be rated at different attractiveness levels.

In general, the correlation between the man’s and the woman’s attractiveness ratings were relatively high, and those who met each other and started dating within a month had relatively similar levels of attractiveness. But the longer the couple knew each other before they started dating, the less likely they were to be matched for attractiveness. For couples who knew each for more than nine months before they started dating, the researchers found no significant correlation in their attractiveness.