Sex Differences in Jealousy:Evolution, Physiology, and Psychology

Buss, Larsen, Westen, and Semmelroth

Paternity Uncertainty

Potential Loss of Investment

The Answer is . . .

“(...) a state that is aroused by a perceived threat to a valued relationship or position and motivates behavior aimed at countering the threat.” (Buss et al., 1992)

“Men indifferent to sexual contact between their mates and other men presumably experienced higher paternity uncertainty, greater investment in competitors’ gametes, and lower reproductive success” than did men who were motivated to attend to cues of infidelity and to act on those cues to increase paternity probability.” (Buss et al., 1992)

Therefore, over time, evolution through means of natural selection managed to “choose” jealous men over the not so jealous.

General Hypothesis: The experience of jealousy is felt differently for men and women because of the different adaptative problems posed to both sexes.

Distinction between sexual and emotional infidelity.

Study 1

N=202 undergraduate students

(a)Imagining your partner forming a deep emotional attachment to another person.

(b) Imagining your partner enjoying passionate sexual intercourse with another person.

(emotional infidelity)

(sexual infidelity)

• 60% of the male sample chose partner’s potential sexual infidelity in comparison to only 17% of the female sample (p < .001)

• 83% of the female sample chose partner’s potential emotional infidelity as the most worriesome of the two options.

Study 2

GOAL: To confirm the previous hypothesis through the use of physiological measures.

Measures of autonomic arousal:– Electrodermal Activity (EDA) via skin

conductance;– Pulse Rate (PR);– Electromyographic (EMG) activity of the

corrugator supercilii muscle.

• Men showed significant increases in EDA during the sexual imagery compared with the emotional imagery (p < .0.5)

• Women showed significant increases in EDA to the emotional infidelity image than to the sexual infidelity image (p < .05)

Electrodermal Activity

Pulse Rate

• Men showed increase in PR to both images, but significantly more so in response to the sexual infidelity image (p < .05)

• Women showed elevated PR to both images, but not differentially so.

Brow Contraction

• Men showed greater brow contraction to the sexual infidelity image, and women showed the opposite pattern (non significant, p < .13, p < .12)

Study 3

GOAL: Replicate and extend the results of the two previous studies by incorporating the experience of being in a committed relationship.

Results:

• Highly significant differences for men but not for women.

• 55% of the men who had experienced a committed relationship reported more distress for sexual infidelity whereas only 29% of the men that didn’t experience it felt distressed by it.

Critical Limitations

• Undergraduate students

• No clear-cut distinction – Emotional vs. Sexual

• Imagined Infidelity ≠ Actual Infidelity

• Swinging (maybe?)