Adaptive radiation, speciation, and reproductive isolation in African weakly electric fishes (genus Campylomormyrus, Mormyridae, Teleostei)

非洲弱电鱼（弯曲鱼属、鳖鱼科、Teleostei）的适应性辐射、物种形成和生殖隔离

• 批准号: 5423887
• 负责人: Professor Dr. Ralph Tiedemann, Ph.D.
• 金额: --
• 依托单位: Department für Nutzpflanzen- und Tierwissenschaften
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2004
• 资助国家: 德国
• 起止时间: 2003-12-31 至 2008-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5423887?language=en
• 关键词: Adaptive; radiation; speciation; reproductive; isolation

The endemic African mormyrids comprise the single largest group of electric fishes worldwide. Their electric organ discharge (EOD) is age, sex, and species specific. We aim at evaluating whether differences in EOD play a key role as prezygotic isolation mechanisms during speciation. Then, we hypothesize that EODs should be particularily divergent among morphologically and genetically similar species. We chose the Campylomormyrus numenius species complex as a model taxon because it contains a still unknown number of morphologically similar species with strikingly divergent EODs. We will combine molecular analysis (mitochondrial cyt b gene, several unlinked nuclear loci) with electrophysiology (electric organ discharge in relation to sex, age, morphotype, and genotype). The significance of EODs for species specific mate recognition will be assessed in mate choice experiments. During our preliminary work, we (1) develped the necessary molecular markers, (2) established the EOD assessment, and (3) optimized the laboratory maintenance of live Campylomormyrus specimens. The ultimate goal of this project is to better understand the relevance of weak electricity in the radiation of African electric fish.

非洲特有的斑鸠鱼是世界上最大的电鱼类群。它们的器官放电 (EOD) 因年龄、性别和物种而异。我们的目的是评估 EOD 的差异是否在物种形成过程中作为合子前隔离机制发挥关键作用。然后，我们假设形态和遗传相似的物种之间的 EOD 应该特别不同。我们选择 Campylomormyrus numenius 物种复合体作为模型分类群，因为它包含数量仍然未知的形态相似的物种，但 EOD 却截然不同。我们将把分子分析（线粒体 cyt b 基因、几个不相关的核位点）与电生理学（与性别、年龄、形态类型和基因型相关的器官放电）结合起来。 EOD 对于物种特异性配偶识别的重要性将在配偶选择实验中进行评估。在我们的前期工作中，我们 (1) 开发了必要的分子标记，(2) 建立了 EOD 评估，以及 (3) 优化了活弯曲霉菌属标本的实验室维护。该项目的最终目标是更好地了解弱电与非洲电鱼辐射的相关性。