DISSERTATION RESEARCH: Trajectories of Genetic Change in Populations With Different Founding Sizes: Time Transects of Daphnia Populations in Two Upstate New York Lakes

种群减少对遗传多样性的长期影响是众所周知的，但很少有研究研究在种群建立后立即研究其遗传多样性的短期变化。 该项目的目标是比较三个物种的食草动物水蚤的遗传多样性的变化，从一个湖泊的少数创始人与第四人口，是由大量的个人成立。 沉积物中的长寿命休眠水蚤卵记录了可以从沉积物岩心重建的种群的年度变化。 研究人员将在浮游化后的几个时间点测量四个“种群”的遗传多样性，以评估种群规模恢复时的变化。水蚤是水生生态系统的重要组成部分，是藻类的控制者和鱼类的食物来源。 一个种群对环境变化的反应能力取决于其遗传多样性的水平。 因此，这项研究将提供重要的见解水蚤如何应对环境变化和影响社区和生态系统过程。 它还将提供理论模型的实证检验，并有助于我们了解自然种群中遗传多样性是如何维持的，这反过来又将促进更适当的管理或保护计划。

Long-term effects of population reductions on genetic diversity are well understood, but few studies have examined short-term changes in genetic diversity in populations immediately after they have been founded. The goal of this project is to compare changes in genetic diversity in three species of the grazing zooplankter Daphnia that recolonized a lake from a small number of founding individuals with a fourth population that was founded by a large number of individuals. Long-lived dormant Daphnia eggs in sediments record annual changes in populations that can be reconstructed from sediment cores. Genetic diversity of each of the four "populations" at several time points following recolonization will be measured to assess changes as the populations recovered in size.Daphnia species are a key component of aquatic ecosystems, serving as a control on algae and a food source for fish. The ability of a population to respond to environmental changes depends on the level of genetic diversity present. This study will thus provide important insights into how Daphnia respond to environmental change and influence community and ecosystem processes. It will also provide empirical tests of theoretical models and contribute to our knowledge about how genetic diversity is maintained in natural populations, which in turn will foster more appropriate management or conservation plans.