Møller A P, Erritzøe J
Laboratoire d'Ecologie, CNRS UMR 7625, Université Pierre et Marie Curie, 7 quai St. Bernard, Case 237, F-75252 Paris Cedex 05, France e-mail:
Taps Old Rectory, DK-6040 Christiansfeld, Denmark, , , , , , DK.
Oecologia. 2000 Mar;122(4):500-504. doi: 10.1007/s004420050972.
Differences in the phenotypic characteristics between individuals falling prey to predators and conspecifics avoiding predation will reflect the intensity of selection on prey. If prey are generally in poor condition, we predicted that they should have an inferior health status in comparison to individuals dying for other reasons. We investigated this prediction for prey and conspecifics that did not die from predation by comparing the size of the spleen, which is an important immune defence organ reflecting one component of immunocompetence, using 18 species of passerine birds and domestic cat Felis catus predators as a model system. Prey had consistently smaller spleens than non-prey, implying that they had weak immune systems. The data set did not indicate that sex or age, month of death, body mass, body condition, liver mass, wing length or tarsus length differed significantly between prey and non-prey. Thus there was little evidence of confounding factors affecting the results. These observations indirectly suggest that disease and parasitism may play an important role in predator-prey interactions.
成为捕食者猎物的个体与避免被捕食的同种个体之间的表型特征差异，将反映出对猎物选择的强度。如果猎物总体状况不佳，我们预测与因其他原因死亡的个体相比，它们的健康状况应该较差。我们以18种雀形目鸟类和家猫（Felis catus）捕食者作为模型系统，通过比较脾脏大小（脾脏是反映免疫能力一个组成部分的重要免疫防御器官），对未死于捕食的猎物和同种个体进行了这一预测的研究。猎物的脾脏一直比非猎物的小，这意味着它们的免疫系统较弱。数据集并未表明猎物和非猎物在性别、年龄、死亡月份、体重、身体状况、肝脏质量、翅长或跗跖长度上存在显著差异。因此，几乎没有证据表明存在影响结果的混杂因素。这些观察结果间接表明，疾病和寄生虫可能在捕食者与猎物的相互作用中发挥重要作用。
