Parasite life cycle evolution and the ecology of trophic interactions

许多寄生虫，其中一些具有医学和兽医学重要性，具有复杂的生命周期，因为它们在最终（最终）宿主中进行有性繁殖之前会感染一个或多个中间宿主作为幼虫。宿主之间的传播通常是营养性的;当前的宿主被下一个宿主吃掉。令人难以置信的是，一些寄生虫在繁殖之前会感染多达四种不同的宿主。为什么寄生虫有如此复杂的生命周期？这是一种令人困惑的生活方式，因为在生命周期的每一步，寄生虫都有可能无法传播给下一个宿主，从而在繁殖之前死亡。该项目旨在更好地了解寄生虫生命周期的演变，并有两个目标：1）重建寄生蠕虫主要群体的生命周期如何演变，以及2）在食物网和觅食生态学的背景下评估生命周期变化（即谁吃谁以及多久吃一次）。这些目标将通过汇编一个关于寄生虫生命周期以及寄生虫宿主在食物网中的位置（即它们的体型和营养级）的综合数据库来实现。该项目将导致更好地了解喂养的相互作用如何塑造寄生虫的策略，它将有助于了解寄生虫的生态作用，考虑到当代环境变化的快速步伐，这是一个重要的研究重点。

Many parasites, some of medical and veterinary importance, have complex life cycles, in that they infect one or more intermediate hosts as larvae before they reproduce sexually in a final (definitive) host. Transmission between hosts is often trophic; the current host is eaten by the next host. Incredibly, some parasites infect up to four different hosts before reproducing. Why do parasites have such complex life cycles? This is a puzzling lifestyle, given that at each step in the life cycle, parasites risk not being transmitted to their next host and thus dying before reproducing. This project aims to better understand the evolution of parasite life cycles and has two objectives: 1) to reconstruct how life cycles evolved in the major groups of parasitic worms, and 2) to evaluate life cycle variation in the context of food webs and foraging ecology (i.e. who eats who and how often). These objectives will be addressed by compiling a comprehensive database on parasite life cycles as well as on the position of the parasites hosts in food webs (i.e. their body sizes and trophic levels). The project will lead to a better appreciation of how feeding interactions shape parasite strategies, and it will help to understand the ecological roles of parasites, an important research priority given the rapid pace of contemporary environmental change.