DISSERTATION RESEARCH: The Role of Mating System in Sperm Competition and Protein Evolution in Agelaius Blackbirds

个体在竞争配偶能力上的差异可以推动进化，这一过程被称为性选择。虽然性选择作用于行为或形态的例子是众所周知的，但对性选择如何在分子水平上影响个体繁殖成功的理解却知之甚少。在雌性与多个雄性交配的物种中，精子会竞争获得雌性的机会？鸡蛋。精子竞争可以导致对精液蛋白（Sfps）的选择，这是雄性在交配过程中转移的一类蛋白质，有助于该雄性成功受精，同时降低其他雄性随后交配的成功率。由于Sfps与精子竞争的关系，在一夫多妻制（精子竞争激烈）的物种中，Sfps的进化可能与一夫一妻制（精子竞争激烈）的物种不同。该项目研究了新大陆黑鹂（Agelaius属）的交配行为与Sfps选择之间的关系，该群体的多样化行为使研究性选择如何影响DNA序列进化成为可能。编码Sfps的基因将被分离出来，以验证这种基因在一夫多妻制物种中比在一夫一妻制物种中进化得更快的假设。这些基因将被存档在NIH序列数据库GenBank中，为研究人员提供未来比较研究的工具。最终，研究结果将阐明选择是如何在广泛的生物尺度上，从分子到有机体水平，将性状联系起来的。指导和推广工作是这个项目不可或缺的一部分。本科学生将通过学习基本的实验技术和撰写原创论文来了解基本的研究过程。结果将在加勒比地区的实地分享，在那里，自然资源机构面临的主要挑战是协调保护的需要与旅游驱动的经济的需要。还将在大学、社区和国家各级广泛宣传工作。

Individual differences in the ability to compete for mates can drive evolution through a process known as sexual selection. While examples of sexual selection acting on behavior or morphology are well known, much less established is the understanding of how sexual selection acts at the molecular level to affect individual reproductive success. In species where females mate with multiple males, sperm compete for access to a female?s eggs. Sperm competition can lead to selection on seminal fluid proteins (Sfps), a class of proteins transferred by a male during mating that aid in successful fertilization by that male while reducing success of subsequent matings by other males. Because of their link to sperm competitiveness, Sfps may evolve differently in species with polygamous mating systems (with high sperm competition) compared to monogamous species (with low sperm competition). This project investigates the relationship between mating behavior and selection on Sfps in New World blackbirds (genus Agelaius), a group whose diverse behavior enables the study of how sexual selection affects DNA sequence evolution. Genes coding for Sfps will be isolated to test the hypothesis that such genes evolve faster in polygamous than in monogamous species. These genes will be archived on the NIH sequence database GenBank, providing researchers with tools for future comparative studies. Ultimately, results will clarify how selection links traits across a wide range of biological scales, from the molecular to organismal level.Mentoring and outreach efforts are integral to this project. Undergraduate students will be introduced to the basic research process by learning fundamental lab techniques and writing original papers. Results will be shared at Caribbean field sites, where a primary challenge facing natural resources agencies is reconciling the need for preservation with those of a tourist-driven economy. Work will also be communicated broadly at the university, community and national levels.