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Upset in response to a Sibling's partner's infidelities
Richard L Michalski1, Todd K Shackelford2, Catherine A Salmon3
1Department of Psychology, Hollins University, P.O. Box 9687, 24020, Roanoke, VA. rmichalski@hollins.edu.
Human Nature (Hawthorne, N.Y.)
|July 17, 2015
Summary
Older adults experience jealousy differently based on sibling gender. Men worry more about a brother's partner's sexual infidelity, while women worry more about a sister's partner's emotional infidelity, supporting evolutionary psychology.
Area of Science:
- Evolutionary Psychology
- Social Psychology
- Human Mating Behavior
Background:
- Jealousy is a complex emotion with evolutionary roots.
- Understanding jealousy in the context of sibling relationships offers insights into reproductive strategies.
- Previous research has explored jealousy related to romantic partners, but less so concerning in-laws.
Purpose of the Study:
- To investigate sex differences in jealousy responses to a sibling's partner's infidelity.
- To test evolutionary predictions versus socialization perspectives on jealousy.
- To examine how the sex of the sibling and the sex of the sibling's partner influence jealousy.
Main Methods:
- Data collected from adult participants with at least one brother and one sister.
- Participants reported levels of upset regarding sexual versus emotional infidelity by a sibling's partner.
- Comparison of responses based on participant sex, sibling sex, and in-law sex.
Main Results:
- Older men and women showed distinct jealousy patterns: men were more upset by a brother's partner's sexual infidelity, while women were more upset by a sister's partner's emotional infidelity.
- Participant sex and in-law sex did not affect upset over a sibling's partner's infidelity.
- Participant sex did influence upset over one's own partner's infidelity.
Conclusions:
- Findings support an evolutionary perspective, highlighting the sex of the sibling (or sibling's partner) as a key factor in jealousy.
- Results challenge a socialization perspective that emphasizes the participant's sex.
- Further research on jealousy and reproductive costs in extended family relationships is warranted.
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