Leveling the Playing Field: Longer Acquaintance Predicts Reduced Assortative Mating on Attractiveness.

Clear empirical demonstrations of the theoretical principles underlying assortative mating remain elusive. This article examines a moderator of assortative mating--how well couple members knew each other before dating--suggested by recent findings related to market-based (i.e., competition) theories. Specifically, competition is pervasive to the extent that people achieve consensus about who possesses desirable qualities (e.g., attractiveness) and who does not. Because consensus is stronger earlier in the acquaintance process, assortative mating based on attractiveness should be stronger among couples who formed a relationship after a short period rather than a long period of acquaintance. A study of 167 couples included measures of how long partners had known each other before dating and whether they had been friends before dating, as well as coders' ratings of physical attractiveness. As predicted, couples revealed stronger evidence of assortative mating to the extent that they knew each other for a short time and were not friends before initiating a romantic relationship.