School of Biological and Behavioural Sciences, Queen Mary University of London, London, UK.
Ecol Lett. 2022 May;25(5):1055-1074. doi: 10.1111/ele.13979. Epub 2022 Mar 1.
Prudent predators catch sufficient prey to sustain their populations but not as much as to undermine their populations' survival. The idea that predators evolve to be prudent has been dismissed in the 1970s, but the arguments invoked then are untenable in the light of modern evolution theory. The evolution of prudent predation has repeatedly been demonstrated in two-species predator-prey metacommunity models. However, the vigorous population fluctuations that these models predict are not widely observed. Here we show that in complex model food webs prudent predation evolves as a result of consumer-mediated ('apparent') competitive exclusion of resources, which disadvantages aggressive consumers and does not generate such fluctuations. We make testable predictions for empirical signatures of this mechanism and its outcomes. Then we discuss how these predictions are borne out across freshwater, marine and terrestrial ecosystems. Demonstrating explanatory power of evolved prudent predation well beyond the question of predator-prey coexistence, the predicted signatures explain unexpected declines of invasive alien species, the shape of stock-recruitment relations of fish, and the clearance rates of pelagic consumers across the latitudinal gradient and 15 orders of magnitude in body mass. Specific research to further test this theory is proposed.
谨慎的捕食者会捕捉足够的猎物来维持其种群数量，但不会多到破坏其种群的生存。谨慎捕食者进化的观点在 20 世纪 70 年代就被摒弃了，但当时提出的论点在现代进化理论的背景下是站不住脚的。在两种物种的捕食者-猎物超社区模型中，谨慎捕食的进化已经被反复证明。然而，这些模型所预测的强烈的种群波动并没有被广泛观察到。在这里，我们表明，在复杂的模型食物网中，谨慎捕食是由于消费者介导的（“明显的”）资源竞争排斥而进化的，这对积极的消费者不利，不会产生这种波动。我们对这种机制及其结果的经验特征提出了可检验的预测。然后，我们讨论了这些预测如何在淡水、海洋和陆地生态系统中得到验证。谨慎捕食的进化解释力远远超出了捕食者-猎物共存的问题，预测的特征解释了外来入侵物种的意外减少、鱼类的种群-补充关系的形状，以及在纬度梯度和 15 个质量数量级上浮游消费者的清除率。我们提出了具体的研究来进一步检验这一理论。
