Evolutionary consequences of interspecific hybridization: Daphnia resting egg banks as biological archives

种间杂交的进化后果：水蚤休眠卵库作为生物档案

• 批准号: 27051794
• 负责人: Professor Dr. Klaus Schwenk
• 金额: --
• 依托单位: Institut für Umweltwissenschaften
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2006
• 资助国家: 德国
• 起止时间: 2005-12-31 至 2006-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/27051794?language=en
• 关键词: Evolutionary; consequences; interspecific; hybridization; Daphnia

Despite many studies on natural interspecific hybridization among plants and animals, few cover long enough time periods to describe the origin and fate of hybrid lineages or to associate levels of interspecific gene flow with environmental conditions. Here we propose to extend our population genetic studies of a Daphnia species complex using resting eggs isolated from sediments of Lake Constance and Lake Greifensee. Initially, only one species (D. hyalina) was found in both lakes (before 1950), later on D. galeata invaded both lakes which resulted subsequently in interspecific hybridization. Based on our preliminary data which provide evidence for a massive hybrid sweep in both populations, we aim to describe the consequences of hybridization (e.g. introgression) during the course of the 20th century (~100 years) using nuclear and mitochondrial DNA data. In addition, we will hatch individuals from several time periods (1960¿s, 1970¿s, 1990¿s and 2000¿s) and test for differential hatching and phenotypic variation over a time period of 40 years. This combined approach of population genetics and phenotypic analyses using resting eggs from lake sediments will allow us to measure the level of reproductive isolation, gene flow, and selection in a species complex during the past century.

尽管有许多关于动植物中种间特异性杂交的研究，但很少有足够长的时间段来描述杂交谱系的起源和命运，或者将种间基因流量的水平与环境条件相关联。在这里，我们建议使用从康斯坦斯湖和格里芬湖的沉积物中分离出的静息卵扩展水壶物种复合物的种群遗传研究。最初，在两个湖泊（1950年之前）中只发现了一个物种（D. hyalina）。基于我们的初步数据，这为两个人群提供了大规模混合扫描的证据，我们旨在使用核和线粒体DNA数据来描述20世纪（〜100年）期间杂交（例如渗入）的后果。此外，我们将从几个时期（1960年代，1970年代和2000年代）中孵化个体，并在40年的时间内测试差异孵化和表型变化。使用湖泊沉积物中静息卵的种群遗传学和表型分析的这种结合方法将使我们能够在过去一个世纪中测量物种复合物中生殖分离，基因流量和选择的水平。