Abstract In social species, conspecific outsiders present various threats to groups and their members. These out-group threats are predicted to affect subsequent within-group interactions (e.g., affiliation and aggression) and individual behavior (e.g., foraging and vigilance decisions). However, experimental investigations of such consequences are rare, especially in natural conditions. We used field-based call playbacks and fecal presentations on habituated wild dwarf mongooses (Helogale parvula)—a cooperatively breeding, territorial species—to examine postinteraction responses to the simulated threat of a rival group. Dwarf mongooses invested more in grooming of groupmates, foraged closer together, and more regularly acted as sentinels (a raised guard) after encountering indicators of rival-group presence compared to control conditions. These behavioral changes likely arise from greater anxiety and, in the case of increased vigilance, the need to seek additional information about the threat. The influence of an out-group threat lasted at least 1 h but individuals of different dominance status and sex responded similarly, potentially because all group members suffer costs if a contest with rivals is lost. Our results provide field-based experimental evidence from wild animals that out-group threats can influence within-group behavior and decision making, and suggest the need for greater consideration of the lasting impacts of social conflict.

中文翻译：

---

实验现场证据表明，群体外的威胁会影响群体内的行为

摘要 在社会物种中，同种外来者对群体及其成员构成各种威胁。这些外群体威胁预计会影响随后的群体内互动（例如，归属和攻击）和个人行为（例如，觅食和警惕决策）。然而，对这种后果的实验研究很少，特别是在自然条件下。我们对已习惯的野矮獴（Helogale parvula）（一种合作繁殖的领地物种）进行现场呼叫回放和粪便展示，以检查对敌对群体的模拟威胁的互动后反应。与对照条件相比，矮獴在梳理群体成员方面投入更多，更紧密地觅食，并且在遇到敌对群体存在迹象后更经常充当哨兵（戒备森严的守卫）。这些行为变化可能是由于更大的焦虑引起的，并且在提高警惕的情况下，需要寻求有关威胁的更多信息。群体外威胁的影响持续至少 1 小时，但不同统治地位和性别的个体反应相似，可能是因为如果与对手的竞争失败，所有群体成员都会遭受损失。我们的研究结果提供了来自野生动物的实地实验证据，表明群体外的威胁可以影响群体内的行为和决策，并表明需要更多地考虑社会冲突的持久影响。