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

在最基本的层面上，进化可以被认为是等位基因频率在几代人中的变化。因此，进化生物学的主要目标之一是解释为什么一些个体比其他个体传递更多的基因。我的研究项目通过阐明影响性选择的因素来解决这一目标，性选择会改变生殖扭曲，从而导致等位基因频率从一代到下一代的变化。直到最近，性选择理论还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(通常是雌性在雄性中选择)和对配偶的竞争(通常是在雄性之间)。然而，遗传和行为研究最近表明，性乱行为在大多数类群中很常见。雌性的多次交配创造了交配后通过精子竞争(不同雄性精子之间为卵子受精而竞争)和神秘的雌性选择(区分使用来自一个雄性的精子而不是另一个雄性的精子，假定对后代健康有遗传好处)继续进行性选择的可能性。因此，生殖适合性现在被认为是由交配前后选择过程中雄性和雌性特征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。在父子关系的交配前和交配后阶段，很少研究性别选择的相对重要性，特别是在单一的交配系统中。我的研究计划将使用外部受精、非基于资源的鱼类交配系统(Chinook鲑鱼和红鱼)来检查交配系统内、种群之间和跨物种之间的产卵前和产卵后的性别选择(从最终和最接近的方式)。总体而言，这一研究项目承诺制作高质量的同行评议出版物，为研究性别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员。

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.