Parasitism and the Maintenance of Genetic Variation in a Partial Parthenogen

活泼9317924这项研究的目的是评估最近发展的寄生虫假说中的一些关键假设，以维持自然种群的遗传多样性和交叉受精。寄生虫假说最关键的假设是，寄生虫对当地常见的寄主基因型施加了选择。如果这个想法是正确的，那么克隆繁殖将会有一个劣势，那就是与任何克隆产生类型的频率成正比。这样的选择要求寄生虫感染有遗传基础，并且寄生虫迅速“追踪”当地常见的宿主基因类型。测试这些想法的理想系统是蜗牛和寄生虫的相互作用，莱弗利博士自1985年以来一直致力于这方面的研究。这种蜗牛和它的寄生虫(吸虫虫)很容易在实验室里饲养。这项研究的目的是确定这种寄生虫是否迅速进化到感染不同的克隆类型，以及它是否可以防止克隆人竞争性地取代交叉受精形式。对维持遗传多样性感兴趣的进化和保护生物学家，以及研究引起人类疾病(例如血吸虫病)的类似寄生虫的流行病学家，都会对研究结果感兴趣。

Lively 9317924 The purpose of this study is to evaluate some of the critical assumptions of the recently developed parasite hypothesis for the maintenance of genetic diversity and cross fertilization in natural populations. The most critical assumption of the parasite hypothesis is that there is selection imposed by parasites against host genotypes that become locally common. If this idea is correct, then there will be a disadvantage to clonal reproduction that is proportional to the frequency of any clonally produced type. Such selection requires that there is a genetic basis to infection by parasites, and that parasites rapidly "track" locally common host genotypes. An ideal system for testing these ideas is the snail-parasite interaction that Dr. Lively has been working on since 1985. The snail and its parasite ( a trematode worm) can be easily reared in the laboratory. The goal of the study is to determine whether the parasite rapidly evolves to infect different clonal types, and whether it can prevent clones from competitively displacing cross-fertilizing forms. The results will be of interest to evolutionary and conservation biologists interested in the maintenance of genetic diversity, as well as epidemiologists working on similar parasites that cause human disease(e.g. Schistosomiasis).