The evolution of extreme cooperation via shared dysphoric experiences

Abstract

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.

Positive experiences of high arousal martial arts rituals are linked to identity fusion and costly pro‐group actions

“…These findings stand in contrast to the emphasis placed on the role of negative experiences in promoting identity fusion bonds , which has received support from some recent empirical studies (Jong et al, 2015;Whitehouse et al, 2017). Crucially, we observed no comparable relationship between negative affect scores and identity fusion (H2b), nor was the negative affect measure predictive of any pro-group sacrifice outcomes.…”

“…Similarly, Newson et al's (2016) study of devoted football fans revealed that experiences of both positive and negative 'key group events' (p. 1) were associated with higher levels of identity fusion. 679-680) and Whitehouse et al (2017) stresses a mediated relationship between negative, potentially traumatic, experiences and identity fusion. The 'shared dysphoria pathway to fusion' model outlined in Whitehouse and Lanman (2014, pp.…”

“…Two independent studies, for example, have reported that individuals who have shared highly arousing negative experiences, such as frontline combat during the Libyan civil war (Whitehouse, McQuinn, Buhrmester, & Swann, 2014) and experiences of violence during the conflict in Northern Ireland (Jong, Whitehouse, Kavanagh, & Lane, 2015), display higher levels of identity fusion with relevant group identities. Finally, a recent multimethods paper has offered converging evidence from an evolutionary mathematical model and a series of correlational and experimental studies that sharing painful experiences is associated with greater willingness to sacrifice for the group and that this relationship is mediated by identity fusion (Whitehouse et al, 2017). Finally, a recent multimethods paper has offered converging evidence from an evolutionary mathematical model and a series of correlational and experimental studies that sharing painful experiences is associated with greater willingness to sacrifice for the group and that this relationship is mediated by identity fusion (Whitehouse et al, 2017).…”

“…The hypotheses that the current study addresses are: H1: Individuals who experience more affectively arousing ritual promotions will report higher levels of identity fusion with their BJJ school (Swann et al, 2012;Whitehouse et al, 2017).…”

Not on my team: Medial prefrontal cortex responses to ingroup fusion and unfair monetary divisions

“…An especially potent mode of group affiliation, highlighted in the recent literature, is identity “fusion” – in which the boundary between group and self is porous, and the individual experiences a “visceral feeling of ‘oneness’ with the group” (Swann & Buhrmester, 2015). Recent work has demonstrated that identity fusion is a powerful motivator of personally costly, progroup behaviors (Whitehouse, McQuinn, Buhrmester, & Swann, 2014; Whitehouse et al., 2017). For example, strongly fused individuals report more willingness to fight and die for their groups (Swann et al., 2014); are especially inclined to endorse sacrificing their lives for fellow in‐group members (but not out‐group members) in trolley dilemma scenarios (Swann, Gomez, Huici, Morales, & Hixon, 2010); and are especially likely to donate personal funds to support group members in difficulty (Buhrmester, Fraser, Lanman, Whitehouse, & Swann, 2015; Swann, Gomez, Dovidio, Hart, & Jetten, 2010).…”