The effects of predation-risk on prey stoichiometry: A meta-analysis

A decade ago, the General Stress Paradigm (GSP) aimed to develop a predictive framework linking predator effects to ecosystem function. The GSP was based on the notion that animals, across taxa, exhibit similar physiological responses to predation risk that divert resources from growth and reproduction [which require N-rich biomolecules (i.e., protein)] to emergency functions [which require C-rich biomolecules (e.g., carbohydrates)]. The GSP predicts that stressed prey should have a greater dietary demand for C-rich resources, a higher body C:N ratio, and elevated N excretion. Now, ten years later, we aim to revisit the GSP— using quantitative meta-analysis to test the original predictions of the GSP and how 1) predator hunting mode, 2) multiple stressors, and 3) prey dietary shifts affect prey stoichiometric responses to predation-risk. Our dataset was consistent with previous work showing that predation-risk increases prey glucocorticoid levels and metabolic rates and decreases prey g...

十年前，通用应激范式（General Stress Paradigm, GSP）旨在构建一套将捕食者效应与生态系统功能相联结的预测性框架。该范式的理论基础为：各类群动物对捕食风险均会展现出相似的生理响应，此类响应会将原本用于生长与繁殖的资源（该过程依赖富氮生物分子，即蛋白质）重新分配至应急生理功能（该功能依赖富碳生物分子，例如碳水化合物）。通用应激范式预测，受捕食风险胁迫的猎物，其对富碳资源的膳食需求会更高，体内碳氮比（C:N）也会升高，且氮排泄量会上升。十年后的当下，我们旨在重新审视该范式——采用定量元分析（quantitative meta-analysis）来验证通用应激范式的原始预测，并探究1）捕食者捕猎模式、2）多重胁迫因子、3）猎物膳食转变这三类因素如何影响猎物面对捕食风险时的化学计量响应。本数据集与既往研究结论一致，即捕食风险会提升猎物的糖皮质激素（glucocorticoid）水平与代谢速率，并降低猎物的g……