JEALOUSLY IN THE LAB: THE EFFECT OF A THIRD PARTY INVESTMENT IN THE ROMANTIC PARTNER

Abstract

In long-term mating, individuals take advantage of all the benefits inherent to a cooperative heterosexual relationship. If we consider that natural selection produced sex differences in the design of adaptations to solve the problems surrounding reproduction, then the design of human jealousy, which is an emotion triggered by lost of a valued relationship, must also be triggered by distinct evoking acts that are specific adaptive challenges for women and men in their exclusivity of their pair-bond. We present a pilot study with a novel method to experimentally trigger the adaptive sex-differences in jealousy. Specifically, we use a game theory protocol in which each member of 28 committed couples (n=56) participated in two interpersonal dictator games against an opposite sex third party and a control condition. In the first dictator game, each member of the dyad performs the role of allocator. In the second game, the members of the couple perform the role of the recipient. The outcome of both games is informed to the partner (jealousy evoking protocol). We hypothesize that i) self-reported evoked jealousy will be greater for women when informed about the outcome of the game in which her partner plays the role of the allocator (the game represents a situation in which their male partner invests resources in another female); and conversely, ii) self-reported jealousy will be greater for male subjects when their partner plays the role of the recipient (the game represents a situation in which his female partner receives resources from another male). The results show that this protocol exerted the expected evocation of jealousy for both sexes. We discuss sex-differences in the treatments and possible alternative modifications to improve the similarity of the game to actual jealousy.