Evolution of Jealousy

What is Jealousy?  We’ve all experienced it …  Powerful and painful  An emotional state that is aroused by a perceived threat to a relationship or position  It motivates behaviors that counter the threat

“Green eyed monster”

Scenario  What would upset or distress you more:  (a) discovering that your partner is forming a deep emotional attachment and confiding and sharing confidences with another? Or  (b) discovering that your partner is enjoying passionate sex with the other person, trying out different sexual positions you had only dreamed about?

The Specific Innate Module Theory  Provided payoff in EEA  Fitness advantage  Innate module, wired-in brain ciruit  Specific sets of brain circuits guides our emotional reaction to threats

Sex Differences in Jealousy  Threats to ancestral man:  Cuckoldry  Uncertainty in paternity  Expending scare resources on another man’s offspring

Sex Differences in Jealousy  Threats to ancestral woman:  Lost resources because of cheating mate  Loss of emotional involvement

Evolutionary Perspective  Jealousy is:  An adaptation  An important passion that helped our ancestors  Emotional wisdom

Self-Report Studies  Buss & colleagues, 1992  Forced-choice method  70% of women indicate emotional infidelity to be more disturbing  40-60% of men report sexual infidelity would be worse

To help determine whether the sex differences in Figure 2 reflected "wired-in," innate modules of male and female jealousy, David DeSteno and his colleagues imposed a cognitive load. Subjects were asked to retain in memory a string of seven digits while answering questions. The load had no effect on males' responses, but females' responses shifted toward picking sexual infidelity as the more powerful jealousy trigger. This shift suggests that women's responses to forced-choice scenarios may reflect inferences or self-presentation strategies. Imposition of Cognitive Load

Physiological Measures of Jealousy  Buss & colleagues  Autonomic nervous system activity  Males heart rates and EDA higher when imagining sexual infidelity  Females showed opposite pattern.

Alternate explanation for development of jealousy  Sibling rivalry  Familiar phenomenon  Avian species  Jealousy in infancy can be elicited by a parent directing attention to Another (Sybil Hart)

Conclusion  Exploring evolutionary roots can be a productive approach to studying jealousy  A large body of evidence supports evolutionary theory of jealousy  It seems likely that different green eyed monsters dwell within men and women, however a monster might first arise in the minds of babies, long before sex and romance emerge