Mating strategies in changing environments

性选择是推动快速进化变化的强大力量。性选择通常在交配后继续进行，当雌性与多个雄性交配时，产生精子竞争和隐性雌性选择（统称为“交配后性选择”PCSS）。PCSS偏爱在交配时策略性地分配射精的雄性。例如，为了获得更高的父权份额，当雄性感觉到自己的配偶与竞争对手交配的风险增加时，它们可能会促进精子转移。了解射精策略及其在PCSS中的作用是该领域的主要目标。然而，大多数研究都是在良好的实验室条件下进行的。在自然界中，动物会遇到压力，例如食物短缺、疾病爆发和恶劣的天气条件。这些压力有可能改变雄性在交配时的转移，以及雌性如何应对，形成最佳策略和PCSS的运作。目的：研究环境应激源对果蝇雄性射精分配的影响及其对雄性射精分配的影响。目的：在两性中，测试在交配时对男性精子和精液分配的影响，以及由此产生的父系结果，a)营养限制b)感染c)温度应激性和及时性我们目前了解到PCSS很普遍。然而，一个常见的脱节是男性策略与由此产生的父权结果之间的联系，这些结果要么没有被衡量，要么结果不一致。我们的想法是，实验室研究中通常使用的非自然的良性条件掩盖了在自然界中有益的适应。现在需要做的是测试暴露于压力源（男女）是否会揭示出男性转移的基因与其获得的父权份额之间的更强联系。这就是这个项目要做的，为性选择领域迈出新的一步，并将其与全球变化联系起来。

BackgroundSexual selection is a potent force that drives rapid evolutionary change. Sexual selection often continues after mating, when females mate with multiple males, generating sperm competition and cryptic female choice (collectively "post-copulatory sexual selection" PCSS). PCSS favours males that strategically allocate ejaculates at mating. E.g., to achieve a higher paternity share, males may boost sperm transfer when they sense a heightened risk that their mates will copulate with rival males. Understanding ejaculate strategies and their role in PCSS is a major goal in the field. However, most studies are conducted under benign lab conditions. In nature, animals will experience stressors, e.g. food shortages, disease outbreaks and adverse weather conditions. These stresses have the potential to alter what males transfer at mating, and how females respond, shaping optimal strategies and the operation of PCSS. ObjectivesOverall Aim: Examine the roles of environmental stressors on male ejaculate allocation and the consequences for PCSS in Drosophila fruit flies.Objectives: in both sexes, to test the effects on male sperm and seminal fluid allocation at mating, and resulting paternity outcomes, ofa) nutritional restriction b) infectionsc) temperature stressNovelty and TimelinessWe currently understand that PCSS is widespread. However, a common disconnect is the link between male strategies, and the resulting paternity outcomes, which are either not measured, or results are inconsistent. Our idea is that the unnaturally benign conditions commonly used in lab studies mask adaptations that would be beneficial in nature. What is needed now is to test whether exposure to stressors (in both sexes) will reveal a stronger link between what males transfer, and the paternity share they achieve. This is what this project will do, forging a novel step forward for the field of sexual selection, and linking it with global change.