Ecology of parasitically modified populations: a case study from a gammarid-trematode system

作者：Fleur Ponton, David G. Biron, C. Joly, Simone Helluy, David Duneau, Frédéric Thomas · 发表于：Marine Ecology Progress Series · 年份：2005 · DOI：10.3354/meps299205 · 被引用次数：33 · 研究领域：Parasite Biology and Host Interactions、Evolution and Genetic Dynamics、Insect symbiosis and bacterial influences

Examples of behavioural manipulation by parasites are numerous but the consequences of these phenomena on the ecology of host populations remains unclear.Through its effect on Gammarus insensibilis behaviour, the salt marsh trematode Microphallus papillorobustus splits its host population into 2 discrete subunits, one living at the surface (infected individuals) and the other living near the bottom (uninfected individuals).Here, we compare several biological characteristics of gammarids from these 2 spatially segregated subunits.Infected females were smaller and thus less fecund than uninfected females.They also had a longer intermoult duration.The mean body size of infected and uninfected males was not significantly different.However, energy reserves were significantly different: infected males possessed higher glycogen and lipid contents and lower glucose content compared to uninfected males.Interestingly, uninfected males living at the surface (those paired with infected females) also displayed higher energy reserves compared to uninfected conspecifics living in the bottom subunit (those paired with uninfected females).In both of the 2 subunits, there was no significant relationship between male sexual performance (measured through the size of their partner) and their levels of energy reserves.The pattern of size-assortative pairing was not significantly different between pairs from the surface and from the bottom, but male sexual performances were on average smaller for m...