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

个体在争夺配偶的能力上的差异可以通过一个被称为性选择的过程来推动进化。虽然性选择影响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生殖成功的理解要少得多。在雌性与多个雄性交配的物种中，精子会竞争获得雌性的卵子？？S卵子。精子竞争可能导致对精液蛋白(SFP)的选择，精液蛋白是一种在交配过程中由雄性转移的蛋白质，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SFP与精子竞争有关，与一夫一妻制物种(低精子竞争)相比，SFP在具有一夫多妻制交配系统(具有高精子竞争)的物种中进化可能不同。这个项目调查了新大陆黑鸟(Agelaius属)在SFP上的交配行为和选择之间的关系，这一群体的不同行为使得研究性选择如何影响DNA序列进化成为可能。将分离编码SFP的基因，以检验这样的假设，即这种基因在一夫多妻制物种中进化得比一夫一妻制物种快。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，结果将阐明选择如何将从分子到生物水平的各种生物尺度的特征联系起来。管理和推广工作是这个项目不可或缺的。本科生将通过学习基础实验室技术和撰写原创论文来了解基础研究过程。结果将在加勒比实地分享，在那里，自然资源机构面临的一个主要挑战是协调保护需求与旅游驱动型经济的需求。工作还将在大学、社区和国家各级广泛交流。

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.