Post-spawning sexual selection and reproductive fitness in fishes

鱼类产卵后性选择和生殖健康

• 批准号: RGPIN-2017-06285
• 负责人: Pitcher, Trevor
• 金额: $ 2.4万
• 依托单位: University of Windsor
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=744810
• 关键词: Post; spawning; sexual; selection; reproductive

Until recently, sexual selection theory assumed most taxa were monogamous and selection was thought to operate mainly via processes prior to copulation (i.e. pre-copulatory selection), namely mate choice (typically females choosing amongst males) and competition for mates (typically males vs. males for access to females). However, genetic and behavioural studies have recently shown that sexual promiscuity is common among most taxa. Multiple mating by females creates the potential for sexual selection to continue after copulation through (i) the competition between sperm of different males for the fertilization of a set of ova (sperm competition) and (ii) the differential use of sperm from one male over another, with a presumed genetic benefit to offspring fitness (cryptic female choice). As a result, reproductive fitness is now understood to be determined by the complex interactions of traits (at both the phenotypic and genotypic level) selected in males and females during episodes of selection before and after copulation. Thus, a central question emerging in sexual selection theory is how do males and females interact in terms of sexual conflict (i.e. due to different reproductive interests) in this post-copulatory selection arena. My long-term objective is to quantify the relative importance of post-copulatory selection on reproductive fitness (from a male and female perspective) in order to gain a better understanding of the evolutionary consequences of sexual selection by building on my previous work and move into innovative new areas of research focusing on Chinook salmon (Oncorhynchus tshawytscha) and redside dace (Clinostomus elongatus) mating systems to examine: (1) whether post-spawning selection reinforces or counteracts pre-spawning selection using experimental crosses (in a wild setting), (2) post-spawning mechanisms that include all ejaculate components for males (sperm, seminal plasma) and females (ovarian fluid and eggs), (3) broad-scale evolutionary patterns of post-spawning sexual selection across populations and species. The research will involve several approaches to test hypotheses including (among others) field research, in-vitro fertilization trials, genomics and microscopy techniques to assess sperm quality. Overall, this research program promises to (i) produce high quality peer-reviewed publications, (ii) create innovative research tools for those who study intrasexual and intersexual selection and (iii) train highly qualified personnel for academia, the private sector or government.

直到最近，性选择理论还假设大多数类群都是一夫一妻制，并且选择被认为主要通过交配前的过程（即交配前选择）进行，即配偶选择（通常是雌性在雄性中选择）和配偶竞争（通常是雄性与雌性）。男性接触女性）。然而，遗传和行为研究最近表明，性乱在大多数类群中都很常见。雌性的多次交配通过以下方式创造了性选择在交配后继续进行的可能性：（i）不同雄性的精子之间为一组卵子受精而竞争（精子竞争）和（ii）对来自一个雄性的精子的不同使用另一种假设是对后代健康有遗传益处（神秘的女性选择）。因此，现在人们认为，生殖适应性是由雄性和雌性在交配前后的选择过程中选择的性状（在表型和基因型水平）的复杂相互作用决定的。因此，性选择理论中出现的一个核心问题是，在交配后选择的舞台上，男性和女性如何在性冲突（即由于不同的生殖利益）方面相互作用。我的长期目标是量化交配后选择对生殖适应性的相对重要性（从男性和女性的角度），以便通过在我之前的工作基础上更好地理解性选择的进化后果，并进入创新的新研究领域，重点关注奇努克鲑鱼 (Oncorhynchus tshawytscha) 和红边鲮鱼 (Clinostomus elongatus) 交配系统，以检查：(1) 产卵后选择是否增强或增强使用实验杂交（在野生环境中）抵消产卵前选择，（2）产卵后机制，包括雄性（精子、精浆）和雌性（卵巢液和卵子）的所有射精成分，（3）大规模跨种群和物种产卵后性选择的进化模式。该研究将涉及多种方法来检验假设，包括（除其他外）实地研究、体外受精试验、基因组学和评估精子质量的显微镜技术。总体而言，该研究计划承诺（i）出版高质量的同行评审出版物，（ii）为研究性内和间性选择的人们创造创新的研究工具，以及（iii）为学术界、私营部门或政府培训高素质人才。