Evolutionary Genetics of Fishes

鱼类的进化遗传学

• 批准号: RGPIN-2018-04803
• 负责人: Ferguson, Moira
• 金额: $ 3.42万
• 依托单位: University of Guelph
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=689471
• 关键词: Evolutionary; Genetics; Fishes

My research program focuses on understanding the factors that influence the evolution of different forms (morphs) that arise in the same population as the result of variation in the environment (food availability and habitat) where the fish live. This is important because we still do not understand how biodiversity is generated and specifically how genetic variation can become partitioned between populations when they begin to diverge genetically into different species. I examine different morphs of Arctic charr (Salvelinus alpinus) from Iceland that differ in body size and shape (phenotype) and live in different environments, which are sometimes in the same lake. Arctic charr continue to be models for this work because of the remarkable variation in their appearance, the ability to capture them from many lakes and produce experimental families. Icelandic charr also have a relatively simple evolutionary history, which makes it easier to disentangle the different factors involved in their evolution. My proposed research is organized into three sections. Firstly, I will test if the body shape and size of fish is the result of environmental features such as food type (natural selection) or random processes (genetic drift and gene flow) not related to the improved performance of fish with a certain phenotype. I will also test if the relationship between phenotype and environment is influenced by population size and the amount of genetic variation of the fish in the population to see if small populations have limited potential to evolve and respond to environmental change. This will involve repeated capture of individually tagged Arctic charr from nineteen small populations that live in lava caves in northern in Iceland. I will also test if the same patterns of morph phenotype and what the fish eat are the same across six Icelandic lakes, which would indicate that body shape is the result of natural selection. Secondly, I will search for genes that influence body morphology and size within morphs and see how these differ between morphs. Here I will look for associations between genes and the phenotype of offspring produced from two parents (families) and wild fish from many unknown families. I will test if the genetic differences between morphs from the same lake are the same as those between morphs in other lakes and if different traits are controlled by different genes. Thirdly, I will test if the genes found to be associated with morphology are located in areas of the genome that have diverged between morphs. This would suggest that the genes discovered are important for the evolution of different morphs. The knowledge generated by this research is essential to tackling the question of whether new species can arise from morphs living together in the same area. **

我的研究项目侧重于了解影响不同形式（变种）进化的因素，这些进化是由于鱼类生活的环境（食物供应和栖息地）的变化而产生的。这很重要，因为我们仍然不了解生物多样性是如何产生的，特别是当种群开始在遗传上分化成不同的物种时，遗传变异是如何在种群之间被分割的。我研究了来自冰岛的北极鲑（Salvelinus alpinus）的不同变种，它们的体型和形状（表现型）不同，生活在不同的环境中，有时生活在同一个湖泊中。北极炭黑一直是这项工作的模型，因为它们在外观上有显著的变化，可以从许多湖泊中捕获它们并产生实验家族。冰岛charr的进化史也相对简单，这使得解开它们进化过程中涉及的不同因素变得更加容易。我的研究计划分为三个部分。首先，我将测试鱼的体型和大小是食物类型（自然选择）等环境特征的结果，还是随机过程（遗传漂变和基因流动）的结果，与具有某种表型的鱼的性能改善无关。我还将测试表现型和环境之间的关系是否受到种群大小和种群中鱼的遗传变异数量的影响，看看小种群是否有有限的进化潜力和对环境变化的反应。这将包括从生活在冰岛北部熔岩洞中的19个小种群中反复捕获单独标记的北极炭。我还将测试在冰岛的六个湖泊中，相同的形态表型模式和鱼吃的东西是否相同，这将表明体型是自然选择的结果。其次，我将在不同的物种中寻找影响身体形态和大小的基因，看看这些基因在不同的物种之间有何不同。在这里，我将寻找基因与来自两个父母（家庭）和来自许多未知家庭的野生鱼类的后代表型之间的关联。我将测试来自同一湖泊的变种之间的遗传差异是否与其他湖泊的变种之间的遗传差异相同，以及不同的性状是否由不同的基因控制。第三，我将测试发现的与形态相关的基因是否位于基因组中不同形态的区域。这表明发现的基因对不同形态的进化很重要。这项研究产生的知识对于解决新物种是否能从生活在同一地区的不同物种中产生的问题至关重要。**