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People feel jealous when their relationship is threatened. Evolutionary psychology helps explain why: Patterns like jealousy exist because they helped humans survive and reproduce back in hunter-gatherer times (i.e., thousands of years ago). Those who exhibited adaptive traits such as jealousy were more likely to survive and reproduce, which shaped the gene pool. People without these traits were less likely to survive or reproduce and their traits gradually died off. The DNA of humans today is therefore made up of qualities that were helpful thousands of years ago.
Men and women evolved unique patterns because of their biological differences, especially related to reproduction. Women require more time than men to reproduce because they get pregnant and raise children. Men on the other hand, can reproduce in minutes because they don’t bear children and could potentially deny paternity (especially in hunter-gatherer times when paternity tests didn’t exist). According to evolutionary psychology, the goal of all humans is to create as many healthy offspring as possible in order to optimize their reproductive success. For women, this requires a significant investment in terms of time and energy. Men however, can spread their genes quickly, so having sex with multiple partners who raise their children is advantageous.1
These biological differences help explain a critical gender difference in jealousy. Women and men respond to jealousy differently. Women seek partners who are invested in child-rearing and have more to lose if their partner chooses someone else. When they feel jealous, they respond by competing with the rival, making themselves into the more attractive partner, and optimizing the relationship. Men, who have more to gain from sex with multiple partners, tend to pull away from their partner when jealous. They are more likely than women to seek the affection of a new partner.
The one thing people must know about jealousy is that women believe men will respond to it in the same way they would. When women want more attention from their partner, they often elicit jealousy in order to get it. This strategy backfires because rather than trying to improve the relationship, men are tempted to withdraw and seek affection from others. Of course, this gender difference is complicated by other factors such as security level and relationship dependence. Secure individuals tend to respond favorably to jealousy by discussing their concerns with a partner and working to resolve the issue whereas insecure-avoidant partners are more likely to retreat. Relationship dependence also influences jealousy responses; those who need the relationship react irrationally because they have more to lose if their partner leaves. But the general rule is: Women and men respond differently to jealousy, which could lead to relationship breakup.
People often ask, is jealousy healthy? The short response is no. Jealousy causes people to feel hurt, angry, sad, and disrespected. It can even lead to violence and homicide. These reactions stem from beliefs that our partner does not value the relationship as much as we do and has failed to honor their commitment. Those who struggle with jealousy can do things to minimize its effects. First, they can make themselves into the most desirable mate possible and then choose a loyal partner. People who recognize their worth and feel as though they would do just fine without the relationship are less likely to experience jealousy. These individuals know that their value is not dependent on the relationship. But keeping jealousy at bay takes both partners. No matter how confident and secure a person, if their partner is flirting with others (or worse!), they are going to feel jealous. In such cases, the best choice is to talk through the issue and if nothing changes, end the relationship.
Remember, jealousy does not change the thoughts or behaviors of your lover; it only changes you. For your own health and happiness, it is important to manage this negative emotion. Jealousy is not a sign of love; it is a sign of dependence. By bolstering your own self worth, jealousy will subside.
1Although biology accounts for some of our behavior, humans are also influenced by cultural factors. It is not socially acceptable or responsible for men to impregnate many women, leaving them to raise children on their own. This type of behavior is now culturally and legally regulated, which interacts with biological influences to determine behavior.
Further reading
Buss, D. M. (2005). The Handbook of Evolutionary Psychology. Hoboken: Wiley.
Guerrero, L. K., & Andersen, P. A. (1998). Jealousy experience and expression in romantic relationships. In P. A. Andersen & L. K. Guerrero (Eds.), Handbook of Communication and Emotion (pp. 155-188). San Diego: Academic Press.
Shettel-Neuber, J., Bryson, J. B., & Young, L. E. (1978). Physical Attractiveness of the "Other Person" and Jealousy. Personality and Social Psychology Bulletin, 4, 612-615.
