When competitors are able to assess the asymmetry in the resource holding potential before interacting, individuals or groups should avoid interacting with stronger opponents, thereby avoiding the energy costs and risk of injury associated with aggressive intergroup encounters. Thus, escalated aggression is expected only between closely matched competitors. Among Argentine tufted capuchin monkeys (Sapajus nigritus), intergroup dominance is decided by the asymmetry in male group size. Using playback experiments, I simulated intergroup encounters with neighboring groups, manipulating both the apparent numerical asymmetry and the resource context. During experimental trials, I recorded the approach behavior of the focal individual, as well as changes in neighbor density and individual travel speed following the presentation of the playback stimulus, to assess whether individual willingness to participate in resource defense was affected by the probability of winning the encounter. In spite of the competitive disadvantage, neither males nor females showed a decreased probability of approach when the numerical odds strongly favored the opposing group. Instead decisions regarding whether to participate appear to be driven primarily by the resource context. Nevertheless, changes in individual behavior during approaches suggest that tufted capuchin monkeys are sensitive to the relative odds. Individuals accelerated less when approaching a larger group, although no changes in neighbor density were apparent. The absence of an effect of the numerical asymmetry on willingness to approach the playback speaker suggests that subordinate groups benefit from engaging in intergroup aggression with larger neighbors, despite the high probability of losing. These encounters may serve to assess the current subjective resource valuation of the neighboring group or limit territorial expansion by large groups by decreasing the marginal value of home range exclusivity. Because these encounters are riskier, however, individuals appear to alter their approaches, becoming more tentative as the numerical odds increasingly favor the opposing group.

中文翻译：

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千方百计：簇绒的卷尾猴的数值评估。

当竞争者能够在互动之前评估资源持有潜力的不对称性时，个人或团体应避免与更强大的对手互动，从而避免能源成本和与激进的团体间遭遇相关的伤害风险。因此，仅在紧密匹配的竞争者之间，攻击性才会升级。在阿根廷丛生的卷尾猴（Sapajus nigritus）中，群体间的优势取决于雄性群体大小的不对称性。通过回放实验，我模拟了与相邻组的组间接触，同时操纵了明显的数值不对称和资源上下文。在实验试验期间，我记录了焦点刺激个体的进近行为，以及在呈现刺激刺激后邻居密度和个体行进速度的变化，评估个人赢得参与资源防御的意愿是否受到赢得对抗的可能性的影响。尽管存在竞争劣势，但当数字赔率强烈有利于对方时，无论男性还是女性都没有降低进近的可能性。相反，有关是否参与的决定似乎主要由资源上下文决定。然而，进近过程中个体行为的变化表明，簇绒的卷尾猴对相对几率很敏感。尽管靠近邻居的密度没有明显变化，但当靠近较大的人群时，个体的加速度会降低。数值不对称性对接近播放讲话者的意愿没有影响，这表明下属群体尽管有很大的失败几率，但仍可从与较大邻居的群体间侵略中受益。这些相遇可能有助于评估当前邻居组的主观资源评估，或通过降低归属范围独有性的边际价值来限制大集团的领土扩张。但是，由于这些相遇的风险较高，因此个人似乎会改变他们的方法，因为数字赔率越来越有利于对立小组，因此变得更具尝试性。这些相遇可能有助于评估当前邻居组的主观资源评估，或通过降低归属范围独有性的边际价值来限制大集团的领土扩张。但是，由于这些相遇的风险较高，因此个人似乎会改变自己的方法，因为数字赔率越来越倾向于对立的小组，因此变得更具尝试性。这些相遇可能有助于评估当前邻居组的主观资源评估，或通过降低归属范围独有性的边际价值来限制大集团的领土扩张。但是，由于这些相遇的风险较高，因此个人似乎会改变他们的方法，因为数字赔率越来越有利于对立小组，因此变得更具尝试性。