Almost all animal species are engaged in predator-prey interactions. These interactions, variable in time and space, favor the emergence and evolution of phenotypic plasticity, which allows prey to fine-tune their phenotype to the current risk of predation. A famous example is the induction of defensive neck-teeth, spines or helmets in some water fleas when they detect cues of predator presence. In general, the response may involve different types of traits (behavioral, morphological, physiological, and life-history traits), alone or in combination. The induced traits may be adaptive anti-predator defenses or reflect more general stress-based responses. Recently, it has been found that predator-induced plasticity occurs not only within but also across generations (transgenerational plasticity), i.e., the phenotype of a generation is influenced by the detection of predator-cues in previous generation(s), even if the current generation is not itself exposed to these cues. In this paper, we aim to review this accumulating literature and propose a current state of key aspects of predator-induced transgenerational plasticity in metazoans. In particular, we review whether patterns of predator-induced transgenerational plasticity depend on the type of traits. We analyze the adaptive value of predator-induced transgenerational plasticity and explore the evidence for its evolution and underlying mechanisms. We also consider its temporal dynamics: what are the time windows during which predator-cues must be detected to be transmitted across generations? Are transgenerational responses in offspring stage-dependent? How many generations does transgenerational plasticity persist? Finally, we discuss other factors highlighted in the literature that influence predator-induced transgenerational plasticity: what are the relative contributions of maternal and paternal exposure to predator-cues in generating transgenerational plasticity? Do transgenerational responses depend on offspring sex? Do they scale with the perceived level of predation risk? This review shows that we are only at the beginning of understanding the processes of predator-induced transgenerational plasticity, and it encourages future research to fill the lack of knowledge highlighted here.

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捕食者-猎物相互作用背景下的跨代可塑性

几乎所有的动物物种都从事捕食者-猎物的相互作用。这些在时间和空间上可变的相互作用有利于表型可塑性的出现和进化，这使得猎物可以根据当前的捕食风险微调它们的表型。一个著名的例子是，当一些水蚤检测到捕食者存在的线索时，它们会诱导出防御性的颈齿、刺或头盔。一般来说，反应可能涉及不同类型的特征（行为、形态、生理和生活史特征），单独或组合。诱发的特征可能是适应性的反捕食者防御或反映更普遍的基于压力的反应。最近，发现捕食者诱导的可塑性不仅发生在代内，而且发生在代际之间（跨代可塑性），即，一代人的表型受到上一代捕食者线索检测的影响，即使当前一代本身并未暴露于这些线索。在本文中，我们旨在回顾这些积累的文献，并提出后生动物捕食者诱导的跨代可塑性的关键方面的现状。特别是，我们回顾了捕食者诱导的跨代可塑性模式是否取决于性状的类型。我们分析了捕食者诱导的跨代可塑性的适应性价值，并探索其进化和潜在机制的证据。我们还考虑了它的时间动态：必须检测到捕食者线索才能跨代传播的时间窗口是多少？后代的跨代反应是否取决于阶段？跨代可塑性能持续多少代？最后，我们讨论了文献中强调的影响捕食者诱导的跨代可塑性的其他因素：母体和父亲暴露于捕食者线索在产生跨代可塑性方面的相对贡献是什么？跨代反应是否取决于后代性别？它们是否与感知的捕食风险水平成比例？这篇综述表明，我们才刚刚开始了解捕食者诱导的跨代可塑性过程，它鼓励未来的研究来填补这里强调的知识缺乏。我们讨论了文献中强调的影响捕食者诱导的跨代可塑性的其他因素：母体和父亲暴露于捕食者线索在产生跨代可塑性方面的相对贡献是什么？跨代反应是否取决于后代性别？它们是否与感知的捕食风险水平成比例？这篇综述表明，我们才刚刚开始了解捕食者诱导的跨代可塑性过程，它鼓励未来的研究来填补这里强调的知识缺乏。我们讨论了文献中强调的影响捕食者诱导的跨代可塑性的其他因素：母体和父亲暴露于捕食者线索在产生跨代可塑性方面的相对贡献是什么？跨代反应是否取决于后代性别？它们是否与感知的捕食风险水平成比例？这篇综述表明，我们对捕食者诱导的跨代可塑性过程的理解才刚刚开始，它鼓励未来的研究来填补这里强调的知识缺乏。母体和父体暴露于捕食者线索在产生跨代可塑性方面的相对贡献是什么？跨代反应是否取决于后代性别？它们是否与感知的捕食风险水平成比例？这篇综述表明，我们对捕食者诱导的跨代可塑性过程的理解才刚刚开始，它鼓励未来的研究来填补这里强调的知识缺乏。母体和父体暴露于捕食者线索在产生跨代可塑性方面的相对贡献是什么？跨代反应是否取决于后代性别？它们是否与感知的捕食风险水平成比例？这篇综述表明，我们才刚刚开始了解捕食者诱导的跨代可塑性过程，它鼓励未来的研究来填补这里强调的知识缺乏。