DISSERATION RESEARCH: Life History Trade-offs: An Investigation of the resource allocation hypothesis in the Florida Scrub-Jay (Aphelocoma coerulescens)

论文研究：生活史的权衡--佛罗里达灌丛鸦资源分配假说的调查&。Boughton University of Memphis人们对当前繁殖和生存之间的假设权衡有相当大的兴趣。然而，调解这种权衡的机制一直难以捉摸。免疫系统是影响生殖和生存的一种机制。虽然在繁殖过程中免疫系统的激活可能会增加存活率，但激活也会使用可能直接用于繁殖的能量资源。本研究的主要目的是在一夫一妻制的长寿合作繁殖佛罗里达灌丛鸦的资源分配假说进行检验，并调查可能作为免疫调节剂的内分泌机制。佛罗里达灌丛鸦是一个独特的模式，以调查资源分配假说，因为在这方面的研究一直局限于迁徙物种的生活史，其特点是相对较短的寿命和时间有限的繁殖季节。定居的性质，寿命长，社会和遗传一夫一妻制的繁殖系统的佛罗里达灌丛周杰伦提供了一个新的和独特的模式来调查假设的繁殖生存权衡。该研究有五个具体目标：（1）在整个年度周期中表征免疫反应，特别注意先前确定的能量瓶颈期，此时预计会发生资源的内部权衡;（2）通过比较补充和非补充地区的松鸦，测量高质量补充食物对免疫功能和繁殖成功的影响;（3）通过比较种鸽和非种鸽的免疫反应，确定种鸽自身是否是免疫抑制的原因;（4）进一步探讨免疫功能与内分泌生理的相互关系（尤其是睾酮、雌激素、皮质酮和催乳素）;以及（5）监测疾病和寄生虫状态以评估它们对免疫功能、生殖努力和存活的影响。这项研究的更广泛的影响是众多的，包括促进共同PI Boughton的研究生培训作为一个专业的研究人员，并作为本科生的导师。在可能的情况下，我们将从生物系招收本科生，孟菲斯的NSF资助计划，本科生环境生物学辅导大学。这些学生将有机会学习野外生物学的方法和技术，如鸟类处理，血液采样和免疫功能测定。研究人员将在佛罗里达灌丛鸦种群的郊区工作时接触公众，从而直接交流基础科学如何调查这种受威胁物种的繁殖成功、疾病暴露和应对机制。公众对研究计划和所进行的研究的认识的基层概念是鼓励公众继续支持资助计划的基础。此外，这两个合作PI定期与当地的观鸟俱乐部和孟菲斯大学的课堂上分享他们的研究成果。这项研究的一个最重要的方面是它与私人阿赫博尔德生物站和长期的佛罗里达擦洗杰伊研究的联系。这种关系促进了与另一位来自圣路易斯密苏里州大学的博士生的合作，他同时正在研究氧自由基假说及其与长寿的关系。这两项研究的共同努力将允许评估两个假设，以解释为什么免疫抑制可能发生在生殖过程中。

Dissertation Research: Life History Trade-offs - An investigation of the resource allocation hypothesis in the Florida Scrub-Jay (Aphelocoma coerulescens) Stephan J. Schoech & Raoul K. BoughtonUniversity of MemphisThere is considerable interest in the hypothesized trade-off between current reproductionand survival. However, the mechanisms that mediate this trade-off have been elusive. One mechanism that can affect both reproduction and survival is the immune system. While activation of the immune system during reproduction will likely increase survival, activation will also use energetic resources that could have been directed towards reproduction. The main objectives of this study are to test the resource allocation hypothesis in the monogamous long-lived cooperatively breeding Florida Scrub-Jay, and to investigate endocrine mechanisms that may function as immuno-modulators. Florida Scrub-Jays are a unique model to investigate the resource allocation hypothesis because research in this area has been restricted to migratory species with life histories that are characterized by relatively short life spans and temporally restricted breeding seasons. The sedentary nature, long life span, and socially and genetically monogamous breeding system of the Florida Scrub-Jay provide for a new and unique model to investigate postulated reproduction-survival trade-offs. The study has five specific objectives: (1) To characterize immune responses throughout the yearly cycle with special attention paid to previously identified energetic bottleneck periods when an internal trade-off of resources would be expected to occur; (2) To measure the effects of high quality supplemental food on immune function and reproductive success by comparing jays from supplemented and non-supplemented territories; (3) To determine whether breeding per se is responsible for immune suppression by comparing immune responses in breeders and nonbreeding helpers; (4) To further investigate the interrelationship between immune function and endocrine physiology (especially, testosterone, estrogen, corticosterone, and prolactin); and (5) to monitor both disease and parasite state to assess their effects upon immune function, reproductive effort, and survival. The broader impacts of this study are numerous and include facilitating co-PI Boughton's graduate training as both a professional researcher and as a mentor to undergraduate students. Where possible, we will recruit undergraduate students from the Department of Biology, University of Memphis' NSF funded program, Undergraduate Mentoring in Environmental Biology. These students will have the opportunity to learn methods and techniques of field biology, such as bird handling, blood sampling, and assays of immune function. Researchers will be exposed to the general public while working on the suburban portions of Florida Scrub-Jay population, allowing direct communication as to how basic science can investigate the reproductive success, disease exposure, and coping mechanisms of this threatened species. The grass roots concept of public awareness of research programs and the research that is undertaken is fundamental to encourage continued public support of funding programs. Additionally, both co-PIs regularly share their research results with local birding clubs and within the classroom at the University of Memphis. A most important aspect of this study is its connection with the private Archbold Biological Station and the long term Florida Scrub-Jay research. This relationship has promoted a partnership with another PhD student from the University of Missouri at St. Louis, who is concurrently investigating the oxygen free radical hypothesis and how it relates to longevity. The combined efforts of both studies will allow evaluation of two hypotheses put forth to explain why immune suppression may occur during reproduction.