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自然种间杂交的研究，但很少有足够长的时间来描述杂交谱系的起源和命运，或将种间基因流动水平与环境条件联系起来。在这里，我们建议扩大我们的人口遗传学研究水蚤物种复杂的使用从博登湖和湖Greifensee沉积物中分离出的休眠卵。最初，只有一个物种（D。hyalina），后来在D. galeata入侵这两个湖泊，随后导致种间杂交。根据我们的初步数据，这两个群体中的大规模杂交扫描提供的证据，我们的目标是描述的结果杂交（例如渐渗）的过程中的20世纪世纪（~100年）使用核和线粒体DNA数据。此外，我们将孵化几个时期（20世纪60年代，70年代，90年代和2000年代）的个体，并在40年的时间内测试差异孵化和表型变异。这种结合了群体遗传学和表型分析的方法，利用湖泊沉积物中的休眠卵，将使我们能够测量过去世纪物种复合体中的生殖隔离、基因流动和选择水平。