Institut des Sciences de l'Evolution, UMR 5554/226 UM2-CNRS-IRD, CC65, Université de Montpellier 2, F-34095 Montpellier, France.
Parasitology. 2011 Nov;138(13):1804-14. doi: 10.1017/S003118201100028X. Epub 2011 Apr 20.
Parasite diversity is hypothesized to act on host life-history traits through investment in immunity. In order to incorporate the diversity of the parasite community that an individual host or a host species may face, two indices can be used: Taxonomic Species Richness and Taxonomic Entropy, where the taxonomic information is incorporated with the taxonomic weight. We tested whether these indices correlate with several morphological traits potentially implicated in immune defence and in reproduction, using data on gastrointestinal helminths and their rodent hosts sampled in Southeast Asia. We found no relationship between parasite diversity indices and either spleen mass or testes size at the intraspecific level, i.e. at the level of individuals. At the interspecific level, we found no relationship between the parasite diversity indices and testes size. However, we found that female spleen mass is significantly influenced by the specific species richness of parasites, whereas male spleen mass is influenced by individual mean parasite diversity indices. We concluded that female spleen mass may have evolved in response to gastrointestinal helminth pressure acting at species levels, while in males, the individual spleen mass could be constrained by other factors, such as the blood storage function of the spleen.
寄生虫多样性被假设通过投资于免疫来影响宿主的生活史特征。为了纳入个体宿主或宿主物种可能面临的寄生虫群落的多样性，可以使用两个指数：分类物种丰富度和分类熵，其中包含了分类信息和分类权重。我们利用东南亚采集的胃肠道寄生虫及其啮齿动物宿主的数据，检验了这些指数是否与几种可能与免疫防御和繁殖有关的形态特征相关。我们发现，在种内水平（即个体水平）上，寄生虫多样性指数与脾脏质量或睾丸大小之间没有关系。在种间水平上，我们发现寄生虫多样性指数与睾丸大小之间没有关系。然而，我们发现雌性脾脏质量受到寄生虫特定物种丰富度的显著影响，而雄性脾脏质量受到个体平均寄生虫多样性指数的影响。我们的结论是，雌性脾脏质量可能是对作用于种水平的胃肠道寄生虫压力的进化反应，而在雄性中，个体脾脏质量可能受到其他因素的限制，如脾脏的血液储存功能。
