Barbaro Nicole, Mogilski Justin K, Shackelford Todd K, Pham Michael N
Department of Psychology, Oakland University, 654 Pioneer Drive, Rochester, MI, 48309, USA.
Hum Nat. 2018 Sep;29(3):328-336. doi: 10.1007/s12110-018-9315-5.
Intra- and intergroup conflict are likely to have been recurrent features of human evolutionary history; however, little research has investigated the factors that affect men's combat alliance decisions. The current study investigated whether features of previous one-on-one combat with an opponent affect men's interest in allying with that opponent for future group combat. Fifty-eight undergraduate men recruited from a psychology department subject pool participated in a one-on-one laboratory fight simulation. We manipulated fight outcome (between-subjects), perceived fighter health asymmetry (within-subjects), and the presence of a witness (within-subjects) over six sets of five rounds of fighting. Following each set, we asked men how interested they would be in allying with their opponent for future group combat. We found that men were more interested in allying with their opponent for future group combat if their opponent won the fight or if a witness was present, but perceived fighter-health asymmetry did not affect men's decision to ally with their opponent. Exploratory analyses revealed a two-way interaction between fight outcome and the presence of a witness, such that winners without a witness present expressed less interest in allying with their opponent for future group combat. Our findings suggest that men attend to the benefits of allying with a man who has demonstrated relatively superior fighting ability. Alliance with a previous opponent for group combat may vary with the relationship value of the opponent and the utility of demonstrating cooperativeness to third-party observers. These findings inform our understanding of coalition formation.
群体内和群体间的冲突很可能是人类进化历史中反复出现的特征；然而，很少有研究调查影响男性战斗联盟决策的因素。当前的研究调查了与对手之前一对一战斗的特征是否会影响男性在未来群体战斗中与该对手结盟的意愿。从心理学系受试者库招募的58名本科男性参与了一对一的实验室战斗模拟。我们在六组每组五轮战斗中操纵了战斗结果（组间因素）、感知到的战斗者健康不对称性（组内因素）以及是否有目击者（组内因素）。每组战斗结束后，我们询问男性他们在未来群体战斗中与对手结盟的意愿有多大。我们发现，如果对手赢得战斗或有目击者在场，男性在未来群体战斗中与对手结盟的意愿会更高，但感知到的战斗者健康不对称性并不影响男性与对手结盟的决定。探索性分析揭示了战斗结果和目击者在场之间的双向交互作用，即没有目击者在场的获胜者在未来群体战斗中与对手结盟的意愿较低。我们的研究结果表明，男性会关注与表现出相对较强战斗能力的男性结盟的好处。与之前的对手结盟参与群体战斗可能会因对手的关系价值以及向第三方观察者展示合作性的效用而有所不同。这些研究结果有助于我们理解联盟的形成。
