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It's not just lunch: extra-pair commensality can trigger sexual jealousy
Kevin M Kniffin1, Brian Wansink
1Dyson School of Applied Economics and Management, Cornell University, Ithaca, New York, United States of America. kmk276@cornell.edu
Plos One
|July 14, 2012
Summary
Sharing a meal with an ex-romantic partner can spark jealousy, suggesting people perceive shared dining as a significant relationship risk. This indicates meals are not viewed as casual interactions in romantic contexts.
Area of Science:
- Social Psychology
- Relationship Science
- Behavioral Economics
Background:
- Romantic relationships often involve navigating social interactions with ex-partners.
- The perceived threat of commensality (sharing meals) in romantic jealousy is not well understood.
Purpose of the Study:
- To investigate whether sharing food, specifically meals, is perceived as a greater relationship risk than other social interactions.
- To examine gender differences in jealousy responses to commensality with ex-partners.
Main Methods:
- Participants rated potential jealousy levels when a romantic partner engaged in food-related activities with an ex-partner.
- Two studies were conducted, assessing participants' own jealousy (Study 1) and their perception of a best friend's jealousy (Study 2).
Main Results:
- Meals consistently elicited higher jealousy than non-eating face-to-face interactions (e.g., coffee).
- This effect was observed across both male and female participants.
- Participants recognized that sharing meals with ex-partners carries significant relationship risks.
Conclusions:
- People perceive shared meals as potentially enhancing cooperation and thus a greater risk in romantic relationships.
- Commensality with ex-partners is not viewed as a benign activity, challenging the notion of 'just lunch'.
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