Pre- and post-spawning sexual selection in fishes: proximate and ultimate explanations of variation in reproductive fitness

鱼类产卵前和产卵后的性选择：生殖适应性变化的直接和最终解释

• 批准号: 341955-2012
• 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: 2012
• 资助国家: 加拿大
• 起止时间: 2012-01-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=507020
• 关键词: Pre; post; spawning; sexual; selection

At the most fundamental level, evolution can be thought of in terms of allele frequency changes over generations. As such, one of the main goals of evolutionary biology is to explain why some individuals pass on more of their genes than others. My research program addresses this goal by elucidating factors that affect sexual selection, which alter reproductive skew and are thus responsible for changes in allele frequencies from one generation to the next. Until recently, sexual selection theory assumed most taxa were monogamous and selection was thought to operate mainly via processes prior to copulation, namely mate choice (typically females choosing amongst males) and competition for mates (typically among males). 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 sperm competition (the competition between sperm of different males for the fertilization of ova) and cryptic female choice (the differential use of sperm from one male over another, with a presumed genetic benefit to offspring fitness). As a result, reproductive fitness is now understood to be determined by the complex interactions of male and female traits during episodes of selection before and after copulation. Thus, a central question emerging in sexual selection theory is whether post-copulatory selection reinforces or counteracts pre-copulatory selection. Measurement of the relative importance of sexual selection during pre- and post-copulatory phases of paternity has rarely been examined, especially within a single mating system. My research program will use external fertilizing, non-resource based fish mating systems (Chinook salmon and redside dace) to examine pre- and post-spawning sexual selection (from both an ultimate and proximate manner) within mating systems, between populations and across species. Overall, this research program promises to produce high quality peer-reviewed publications, create innovative research tools for those who study sexual selection and train highly qualified personnel for academia, the private sector and government.

在最基本的层面上，进化可以被认为是等位基因频率在世代之间的变化。因此，进化生物学的主要目标之一是解释为什么有些个体比其他人传递更多的基因。我的研究计划通过阐明影响性选择的因素来实现这一目标，这些因素改变了生殖偏斜，从而导致了等位基因频率从一代到下一代的变化。直到最近，性选择理论假设大多数分类群是一夫一妻制的，选择被认为主要通过交配前的过程进行，即配偶选择（通常是雌性在雄性之间选择）和配偶竞争（通常是雄性之间）。然而，最近的遗传和行为研究表明，性滥交在大多数分类群中很常见。雌性的多次交配创造了交配后通过精子竞争（不同雄性的精子之间为卵子受精而进行的竞争）和神秘的雌性选择（对一个雄性的精子的不同使用，假定对后代的遗传有益）继续进行性选择的可能性。因此，生殖适合度现在被理解为是由交配前后的选择过程中雄性和雌性性状的复杂相互作用决定的。因此，性选择理论中出现的一个中心问题是，交配后的选择是加强还是抵消交配前的选择。测量的相对重要性，性选择在交配前和交配后阶段的父权很少被检查，特别是在一个单一的交配系统。我的研究计划将使用外部的非资源型鱼类交配系统（大鳞鲑和红边？）检查前和产卵后的性选择（从最终和接近的方式）交配系统内，种群之间和跨物种。总的来说，该研究计划有望产生高质量的同行评审出版物，为那些研究性选择的人创造创新的研究工具，并为学术界，私营部门和政府培训高素质的人才。