Effect of Predator‐Prey Phylogenetic Similarity on the Fitness Consequences of Predation: A Trade‐off between Nutrition and Disease?
Effect of Predator‐Prey Phylogenetic Similarity on the Fitness Consequences of Predation: A Trade‐off between Nutrition and Disease?
复制标题
捕食者-被捕食者系统发育相似性对捕食适应性后果的影响：营养与疾病之间的权衡？
作者：
D. Pfennig
觅食行为的一个很大程度上被忽视的方面是，捕食的成本和收益是否随着捕食者和猎物之间的系统发育(即遗传)相似性而变化。与捕食者具有不同系统发育相似性的猎物的价值可能不同，因为病原体传播的风险和猎物的营养质量通常都随着捕食者和猎物之间的系统发育相似性的降低而下降。我在实验中评估了这一假说，方法是喂食杂食性的扇形蟾蜍蝌蚪(Spea ombirons、Spea Multiicata和Scaphiopus Couchii)，要么是同种蝌蚪，要么是同等质量的三种不同物种的异种猎物，所有这些猎物都含有自然产生的细菌。我还检查了斯帕蝌蚪喜欢哪种猎物。我发现，这三种蝌蚪在捕食与捕食者有中等系统发育相似性的猎物时表现最好，也更喜欢吃。中等系统发育相似性的猎物可能为捕食者提供最大的适合性好处，因为这种猎物平衡了近亲猎物的营养利益和近亲个体之间寄生虫传播的成本。
A largely neglected aspect of foraging behavior is whether the costs and benefits of predation vary as a function of phylogenetic (i.e., genetic) similarity between predator and prey. Prey of varying phylogenetic similarities to predators might differ in value because both the risk of pathogen transmission and the nutritional quality of prey typically decline with decreasing phylogenetic similarity between predator and prey. I experimentally evaluated this hypothesis by feeding omnivorous spadefoot toad tadpoles (Spea bombifrons, Spea multiplicata, and Scaphiopus couchii) either conspecific tadpoles or an equal mass of three different species of heterospecific prey, all of which contained naturally occurring bacteria. I also examined which prey species Spea tadpoles preferred. I found that all three species of tadpoles performed best on, and preferred to eat, prey that were of intermediate phylogenetic similarity to the predators. Prey of intermediate phylogenetic similarity may provide the greatest fitness benefits to predators because such prey balance the nutritional benefits of closely related prey with the cost of parasite transmission between closely related individuals.