Playing to an audience: the social environment influences aggression and victory displays

Animal behaviour studies have begun to incorporate the influence of the social environment, providing new opportunities for studying signal strategies and evolution. We examined how the presence and sex of an audience influenced aggression and victory display behaviour in field-captured and lab-reared field crickets (Gryllus veletis). Audience type, rearing environment, and their interaction were important predictors in all model sets. Thus audience type may impose different costs and benefits for competing males depending on whether they are socially experienced or not. Our results suggest that field-captured winners, in particular, dynamically adjust their contest behaviour to potentially gain a reproductive benefit via female eavesdropping and may deter future aggression from rivals by advertising their aggressiveness and victories.

动物行为学研究现已逐步纳入社会环境的影响因素，为信号策略与演化的相关研究开辟了全新路径。本研究以野外捕获及实验室饲养的田野蟋蟀（Gryllus veletis）为研究对象，探究了围观个体的存在与否及其性别，如何影响受试个体的攻击行为与胜利展示行为。围观个体类型、饲养环境及其交互作用，在所有模型集中均为重要的预测变量。据此可知，依据雄性竞争者是否具备社会经历，不同类型的围观个体可能会为其带来差异化的成本与收益。本研究结果显示，尤其是野外捕获的获胜雄性蟋蟀，会动态调整其竞争行为，通过雌性个体的窃听行为潜在获取繁殖收益；同时还可通过彰显自身的攻击性与获胜经历，威慑后续竞争者的攻击行为。