Maintenance of Variation in Sexually Selected Traits: a Nutritional Ecology Approach

维持性选择特征的变异：营养生态学方法

• 批准号: 327856-2012
• 负责人: Bertram, Susan
• 金额: $ 1.53万
• 依托单位: Carleton University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2013
• 资助国家: 加拿大
• 起止时间: 2013-01-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=527109
• 关键词: Maintenance; Variation; Sexually; Selected; Traits

How genetic variation is maintained in traits that enhance fitness remains a fundamental dilemma in evolutionary biology. Several major theories have been put forth to explain the persistence of genetic variance including genic capture, frequency dependent fitness, fluctuating selection, genotype-by-environment interactions, genotype-by-genotype interactions, heterosis, and antagonistic pleiotropy. My students and I are testing some of these theories using an animal behaviour approach that incorporates tools from nutritional ecology, ecological physiology, and quantitative genetics. Our laboratory-based empirical research quantifies the phenotypic and genetically based variation in condition, life-history traits, and sexually selected traits and determines how this variation is influenced by diet and physiology. Our first three research goals lay the foundation needed to test hypotheses for maintaining variation in fitness traits. We will estimate the structure of sexual traits and female preference functions to understand how traits are likely to experience selection; quantify how diet affects sexual traits to determine their condition-dependent nature; and assess how diet influences the physiological foundations of sexual trait variation. We will then test the genic capture hypothesis and quantify whether females receive indirect benefits from mating with preferred mates. Lastly, we will test whether frequency-dependent fitness can maintain variance in these sexual traits. Together this work will determine the multivariate structure of the sexual traits, their condition-dependent nature, their physiological and genetic underpinnings, whether females receive indirect benefits, and the potential for frequency-dependent fitness. Overall, our research will explicitly test two of the above theories for the maintenance of high genetic variance - genic capture and frequency-dependent fitness. Long-term, the overarching goal of my research program is to contribute to a more complete understanding of how high genetic variance is maintained in traits that enhance fitness.

如何在增强适合度的特征中保持遗传变异仍然是进化生物学中的一个根本难题。人们提出了几种主要的理论来解释遗传变异的持久性，包括基因捕获、频率依赖的适合度、波动选择、基因与环境的互作、基因与基因的互作、杂种优势和拮抗多效性。我和我的学生正在使用一种动物行为方法来测试其中一些理论，该方法结合了营养生态学、生态生理学和数量遗传学的工具。我们基于实验室的经验研究量化了条件、生活史特征和性选择特征的表型和基于遗传的变异，并确定了这种变异如何受到饮食和生理的影响。我们的前三个研究目标奠定了测试保持健康特征变异的假设所需的基础。我们将估计性特征的结构和女性偏好函数，以了解特征可能如何经历选择；量化饮食如何影响性特征，以确定其条件依赖性；以及评估饮食如何影响性特征变异的生理基础。然后，我们将测试基因捕获假说，并量化雌性是否从与首选配偶的交配中获得间接好处。最后，我们将测试频率依赖的适合度是否可以保持这些性特征的差异。这项工作将共同决定性征的多变量结构，它们的条件依赖性质，它们的生理和遗传基础，女性是否获得间接好处，以及频率依赖健康的可能性。总体而言，我们的研究将明确测试上述两种保持高遗传变异的理论-基因捕获和频率依赖适应度。从长远来看，我的研究计划的首要目标是帮助更全面地理解增强健康的特征中保持高度遗传变异的原因。