Abstract
Infidelity in romantic relationships can be devastating, and can cause many complex emotional reactions. The Jealousy as a Specific Innate Module (JSIM) hypothesis posits that due to differing reproductive pressures over evolutionary history, men and women have evolved different mechanisms to respond to infidelity. JSIM proposes that men, due to fears of cuckoldry, will respond with intense jealousy to a partner's sexual infidelity. It proposes that women, who are certain of their maternity but may suffer severe consequences if their mate falls in love with another and diverts his resources elsewhere, will respond with intense jealousy to emotional infidelity. These gender effects were examined in a study of participants who had recently been cheated on sexually, emotionally, or both, by romantic partners. Distress, forgiveness, and couple identity were measured. Results among actual victims of infidelity failed to support the JSIM hypotheses. Men and women responded with similar levels of distress to both types of infidelity. Both men and women were less forgiving as sexual infidelity severity increased, yet the severity of sexual infidelity was associated positively and significantly with less forgiveness for women, and it was associated less positively and non-significantly with less forgiveness for men. Men reported more couple identity after infidelity than did women. In a larger sample that used hypothetical scenarios, it was found that men responded with more upset to sexual infidelity and women responded with more upset to emotional infidelity when using a forced choice method.