Experimental Evolution of Insect Nuptial Food Gifts and Female Responses

昆虫对社会有着巨大的经济影响，它们作为农业害虫和疾病传播者的作用是负面的，而作为各种农产品的重要授粉者是正面的。它们的影响力因其快速繁殖和大量繁殖的能力而扩大，这取决于每只雌性动物所能产生的后代数量。雌性在繁殖过程中的差异部分由雄性控制，雄性可以通过转移影响其生理和交配过程中的感受性的化学物质来操纵雌性。该项目涉及基础研究，以确定影响雌性交配行为的雄性转移的化学物质，潜在的基因以及雌性保护自己免受这些物质影响的机制。这些研究可能导致抑制雌性生殖的产品，并可用于安全有效的昆虫生物防治。该项目还将通过支持本科生、研究生和博士后学生，为培养下一代科学家做出贡献。这些学生将通过科学奖学金传播他们的工作，并将参加以公众对昆虫的迷恋为中心的社区外展计划。这些活动包括培养小学生对科学的兴趣，以及通过向中学教师提供昆虫研究资源来提高科学素养。配偶食物礼物是雄性给予雌性的食物，是各种昆虫交配系统的一个组成部分。在装饰蟋蟀中，婚礼食物礼物采取精囊的形式，这是一种凝胶状的物质，形成雄性精囊的一部分，由雌性食用。虽然婚姻礼物通过最大化精子转移来提高男性的健身兴趣，但它们对女性健身的影响仍然不清楚。研究人员将采用实验进化来探索男性和女性目标冲突在推动男性婚礼礼物的化学成分进化以及女性对装饰蟋蟀的反应中的作用。具体来说，他们将通过操纵重复种群中男性和女性的比例来改变选择和冲突的强度，然后同时监测男性和女性的进化反应。他们将使用气相色谱和质谱来跟踪精叶游离氨基酸谱的进化修饰，并靶向基因表达以评估关键基因的变化。将使用行为测定来评估礼物的味觉吸引力，并将使用比较转录组学方法来表征来自不同选择系的雌性的脑和肠组织中的差异基因表达。通过将强大的实验进化设计与最先进的功能基因组学相结合，他们的目标是提供一个最全面的检查，以了解选择和冲突如何有助于昆虫广泛的生殖适应的进化。

Insects have an enormous economic impact on society, negatively through their roles as agricultural pests and transmitters of disease, and positively as critical pollinators of a wide range of agricultural products. Their influence is amplified by their ability to reproduce rapidly and in great numbers, which is determined by the number of offspring each female can produce. Differences between females in their reproduction is partially controlled by males, who can manipulate females by transferring chemicals that influence their physiology and receptivity during mating. This project involves fundamental research to identify the chemicals transferred by males that influence female mating behavior, the underlying genes, and the mechanisms by which females protect themselves from these substances. These studies may lead to products that inhibit female reproduction, and which can be used for safe and effective biological control of insects. The project will also contribute to the training of the next generation of scientists by supporting undergraduate, graduate, and post-doctoral students. These students will disseminate their work through scientific scholarship, and will participate in community outreach programs centered on the public's fascination with insects. These include activities that foster an interest in science in elementary-school children and that enhance scientific literacy by providing resources for the study of insects to high school teachers. Nuptial food gifts are food items given by males to females and are an integral feature of various insect mating systems. In decorated crickets, nuptial food gifts take the form of a spermatophylax, a gelatinous mass forming part of the male's spermatophore and consumed by the female. Although nuptial gifts advance the fitness interests of males by maximizing sperm transfer, their effect on the fitness of females remains unclear. The researchers will employ experimental evolution to explore the role of conflicting male and female goals in driving the evolution of the chemical composition of male nuptial gifts and female responses to them in decorated crickets. Specifically, they will vary the intensity of selection and conflict by manipulating the ratio of males and females in replicate populations, and then monitor, simultaneously, the evolutionary responses of males and females. They will use gas chromatography and mass spectrometry to track evolutionary modifications in the free amino acid profile of the spermatophylax, and targeted gene expression to assess changes in key genes. Female evolutionary responses will be assessed using behavioral assays to assess the gustatory appeal of gifts, and a comparative transcriptomics approach will be used to characterize differential gene expression in brain and gut tissue of females from different selection lines. By coupling a powerful experimental evolution design with state-of-the art functional genomics, they aim to provide one of the most comprehensive examinations of how selection and conflict contribute to the evolution of a widespread reproductive adaptation in insects.