Mating Preference Evolution: A Nutritional Ecology Approach

寻找配偶可能代价高昂，因为这会让雌性暴露在捕食者面前，并占用雌性完成其他任务的时间。我的主要研究目标是理解为什么面对这些代价，择偶偏好会进化。大多数间接适应性利益假说认为，交配偏好的进化是因为精心设计的特征反映了更高的后代存活率或繁殖成功率（良好的基因）。******项目1通过评估营养如何影响与表现特征变化相关的生理和认知基础，为测试第二性特征与条件相关的理论奠定了基础。由能量储存差异、肌肉代谢能力或代谢率引起的生理能力差异可能是条件变化的基础，因此我将量化营养如何影响生理和代谢表现，以及对复杂性状和偏好的相应影响。另外，条件的变化可能是由于个体收集、保留和使用信息的方式不同造成的，因此我将量化营养如何影响认知表现以及对复杂特征和偏好的相应影响。总之，这些实验将回答“条件是什么？”******项目2和3通过确定性选择特征是否反映压力下的生存能力，以及与非常有吸引力的雄性交配的雌性是否会产生具有更高生存能力或生殖价值的后代，直接测试了基于生存能力的指标理论。由于基于生存能力的指标模型假设优质雄性比劣质雄性在性状精化成本上遭受的损失要小，因此压力源对优质雄性的生存影响应该小于劣质雄性。我将添加与精细性状无关的压力源，并量化精细性状是否影响生存（项目2）。我还将测试这一预测，即女性从与首选伴侣交配中获得间接的健康益处（项目3）。通过重复的交配比赛，我将根据雌性对雄性的偏好程度对它们进行排名，然后将雌性与最受欢迎和最不受欢迎的雄性交配。我将测试最受青睐的雄性和最不受青睐的雄性的复杂性状是否不同，以及最受青睐的雄性的后代是否比最不受青睐的雄性的后代有更高的生存能力，产生更复杂的性状，有更强的偏好，有更高的繁殖力，有更高的存活率。Project 3还可以让我区分出基因和环境引起的变异，测试环境引起的条件变异是否可以从父亲遗传给后代。******通过整合行为学、生态学、生理学、心理学、进化和遗传学的方法，我的研究项目将帮助生物学家了解交配偏好的进化，以及赋予适应性的特征是如何维持变异的。

Finding a mate can be costly as it exposes females to predators and takes time away from other tasks. Understanding why mate preferences have evolved in the face of these costs is my primary research goal. Most indirect-fitness benefits hypotheses suggest mating preferences evolve because elaborate traits reflect greater offspring survival or reproductive success (good genes). ******Project 1 lays the foundation required to test the theory that secondary sexual traits are linked to condition by assessing how nutrition influences the physiological and cognitive foundations associated with performance trait variation. Differences in physiological capacity resulting from energy store disparities, muscle metabolic capacity, or metabolic rate may underlie variation in condition, so I will quantify how nutrition impacts physiological and metabolic performance and the corresponding impact on elaborate traits and preferences. Alternatively, variation in condition may result from differences in how individuals collect, retain and use information, so I will quantify how nutrition impacts cognitive performance and the corresponding impact on elaborate traits and preferences. Together, these experiments will answer “What is condition?”******Projects 2 & 3 directly test the viability-based indicator theory by determining whether sexually selected traits reflect survival under stress and whether females that mate with very attractive males produce offspring with higher viability or reproductive values. Because viability-based indicator models assume high quality males suffer less than low quality males from the costs of trait elaboration, stressors should impact survival of high quality males less than low quality males. I will add stressors unrelated to elaborate traits and quantify whether trait elaboration influences survival (Project 2). I will also test the prediction that females receive indirect-fitness benefits from mating with preferred mates (Project 3). Using a repetitive mating tournament, I will rank-order males based on how strongly females prefer them, and then mate females to the most and least preferred males. I will test whether most and least preferred males differ in their elaborate traits, and whether the offspring of most preferred males have higher viability, produce more elaborate traits, have stronger preferences, have higher fecundity, and have higher survival than the offspring of least preferred males. Project 3 will also enable me to partition out the variance due to genes and environment and test whether environmentally induced variation in condition can be transmitted from father to offspring.******By integrating approaches from behaviour, ecology, physiology, psychology, evolution and genetics, my research program will help biologists understand the evolution of mating preferences and how variation is maintained in traits that confer fitness.