Interacting with the enemy: indirect effects of personality on conspecific aggression in crickets

In animal contests, individuals respond plastically to the phenotypes of the opponents that they confront. These “opponent”—or “indirect”—effects are often repeatable, for example, certain opponents consistently elicit more or less aggressiveness in others. “Personality” (repeatable among-individual variation in behavior) has been proposed as an important source of indirect effects. Here, we repeatedly assayed aggressiveness of wild-caught adult male field crickets Gryllus campestris in staged dyadic fights, measuring aggressiveness of both contestants. Measurements of their personality in nonsocial contexts (activity and exploration behavior) enabled us to ask whether personality caused indirect effects on aggressiveness. Activity, exploration, and aggressiveness were positively associated into a behavioral syndrome eliciting aggressiveness in conspecifics, providing direct evidence for the role of personality in causing indirect effects. Our findings imply that a multivariate view of ...在动物争斗场景中，个体可依据遭遇对手的表型做出可塑性响应。这类“对手效应”或“间接效应”通常具有可重复性：例如，特定对手总能让其他个体表现出或强或弱的攻击性。“个性（Personality）”（即个体间可重复的行为差异）已被学界提出为间接效应的重要来源之一。本研究针对野外捕获的成年雄性田野蟋蟀（Gryllus campestris）开展标准化配对争斗实验，重复测定其攻击性，并同时记录两名争斗者的攻击性表现。通过测定这些蟋蟀在非社会情境下的个性特征（活动与探索行为），我们得以探究个性是否会对攻击性产生间接效应。活动、探索与攻击性三者呈正相关，共同构成了可诱发同种个体攻击性的行为综合征（behavioral syndrome），直接证明了个性在介导间接效应中的作用。本研究结果表明，需以多变量视角审视……