Data from: Naive juveniles are more likely to become breeders after witnessing predator mobbing

Responding appropriately during the first predatory attack in life is often critical for survival. In many social species, naive juveniles acquire this skill from conspecifics, but its fitness consequences remain virtually unknown. Here we experimentally demonstrate how naive juvenile Siberian jays (Perisoreus infaustus) derive a long-term fitness benefit from witnessing knowledgeable adults mobbing their principal predator, the goshawk (Accipiter gentilis). Siberian jays live in family groups of two to six individuals that also can include unrelated nonbreeders. Field observations showed that Siberian jays encounter predators only rarely, and, indeed, naive juveniles do not respond to predator models when on their own but do when observing other individuals mobbing them. Predator exposure experiments demonstrated that naive juveniles had a substantially higher first-winter survival after observing knowledgeable group members mobbing a goshawk model, increasing their likelihood of acquiring a breeding position later in life. Previous research showed that naive individuals may learn from others how to respond to predators, care for offspring, or choose mates, generally assuming that social learning has long-term fitness consequences without empirical evidence. Our results demonstrate a long-term fitness benefit of vertical social learning for naive individuals in the wild, emphasizing its evolutionary importance in animals, including humans.

生命中首次遭遇捕食者攻击时做出恰当应对，通常是生存的关键。在诸多社会性物种中，无经验的幼体会从同种个体处习得这项技能，但该行为对适合度（fitness）的影响至今几乎仍不明确。本研究通过实验证实，无经验的幼年西伯利亚松鸦（Perisoreus infaustus）可通过观察具备相关经验的成年个体对其主要捕食者——苍鹰（Accipiter gentilis）进行示威猛扑，获得长期的适合度收益。西伯利亚松鸦以2至6只个体组成家庭群，群体中还可能包含无亲缘关系的非繁殖个体。野外观察结果显示，西伯利亚松鸦极少遭遇捕食者；事实上，无经验的幼体在独处时不会对捕食者模型做出反应，但在观察其他个体对捕食者示威猛扑时则会做出回应。捕食者暴露实验表明，观察过同群成年个体对苍鹰模型进行示威猛扑的无经验幼体，其首个越冬季的存活率显著更高，这提升了它们日后获得繁殖地位的可能性。既往研究表明，无经验的个体可通过观察同类学会应对捕食者、抚育后代或选择配偶，但这类研究通常在缺乏实证的前提下，默认社会学习会带来长期的适合度相关影响。本研究结果证实，野外环境下无经验个体通过垂直社会学习可获得长期适合度收益，凸显了该行为在包括人类在内的动物类群中的进化重要性。