Graduate Program in Ecology and Evolution, Rutgers University, New Brunswick, New Jersey, United States of America.
PLoS One. 2011;6(10):e26798. doi: 10.1371/journal.pone.0026798. Epub 2011 Oct 25.
Parasites significantly alter topological metrics describing food web structure, yet few studies have explored the relationship between food web topology and parasite diversity.
METHODS/PRINCIPAL FINDINGS: This study uses quantitative metrics describing network structure to investigate the relationship between the topology of the host food web and parasite diversity. Food webs were constructed for four restored brackish marshes that vary in species diversity, time post restoration and levels of parasitism. Our results show that the topology of the food web in each brackish marsh is highly nested, with clusters of generalists forming a distinct modular structure. The most consistent predictors of parasite diversity within a host were: trophic generality, and eigenvector centrality. These metrics indicate that parasites preferentially colonise host species that are highly connected, and within modules of tightly interacting species in the food web network.
CONCLUSIONS/SIGNIFICANCE: These results suggest that highly connected free-living species within the food web may represent stable trophic relationships that allow for the persistence of complex parasite life cycles. Our data demonstrate that the structure of host food webs can have a significant effect on the establishment of parasites, and on the potential for evolution of complex parasite life cycles.
寄生虫会显著改变描述食物网结构的拓扑度量，但很少有研究探索食物网拓扑结构与寄生虫多样性之间的关系。
方法/主要发现：本研究使用描述网络结构的定量指标来研究宿主食物网拓扑结构与寄生虫多样性之间的关系。为四个不同物种多样性、恢复后时间和寄生虫感染水平的咸水沼泽构建了食物网。我们的结果表明，每个咸水沼泽的食物网拓扑结构高度嵌套，具有一般专家的聚类形成了明显的模块化结构。宿主内寄生虫多样性的最一致预测因子是：营养一般性和特征向量中心性。这些指标表明寄生虫优先定殖在高度连接的宿主物种上，以及食物网网络中紧密相互作用的物种模块内。
结论/意义：这些结果表明，食物网中高度连接的自由生活物种可能代表稳定的营养关系，允许复杂寄生虫生命周期的持续存在。我们的数据表明，宿主食物网的结构可以对寄生虫的建立和复杂寄生虫生命周期进化的潜力产生重大影响。
