The evolution of extreme cooperation via shared dysphoric experiences

Harvey Whitehouse, Jonathan Jong, Michael Buhrmester, Angel Gomez, Brock Bastian, Christopher Kavanagh, Martha Newson, Miriam Matthews, Jonathan Lanman, Ryan McKay, Sergey Gavrilets

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Willingness to lay down one’s life for a group of non-kin, well documented historically and ethnographically, represents an evolutionary puzzle. Building on research in social psychology, we develop a mathematical model showing how conditioning cooperation on previous shared experience can allow individually costly pro-group behavior to evolve. The model generates a series of predictions that we then test empirically in a range of special sample populations (including military veterans, college fraternity/sorority members, football fans, martial arts practitioners, and twins). Our empirical results show that sharing painful experiences produces “identity fusion” – a visceral sense of oneness – which in turn can motivate self-sacrifice, including willingness to fight and die for the group. Practically, our account of how shared dysphoric experiences produce identity fusion helps us better understand such pressing social issues as suicide terrorism, holy wars, sectarian violence, gang-related violence, and other forms of intergroup conflict.
Original languageEnglish
Article number44292
Pages (from-to)1-10
Number of pages10
JournalScientific Reports
Publication statusPublished - 14 Mar 2017

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