Collaborative Research: Social Environment Effects on Hormones and the Integrated Behavioral Phenotype

动物必须调整自己的行为和其他特征来适应不断变化的社会环境。例如，个体用来吸引配偶和繁殖的策略和信号通常取决于个体相对于群体中其他个体的社会地位，而这种地位会随着群体构成的变化和/或其他个体的地位变化而波动。因此，这些行为和信号背后的荷尔蒙和遗传机制可能对社会条件很敏感。然而，我们对这些机制知之甚少，特别是对生活在自然条件下的野生种群。该项目将研究允许行为灵活性的机制，以及这些机制演变的方式，以澳大利亚细尾鹩莺（属Malurus）为模型系统。这些被研究的物种非常适合这项研究，因为它们在个体和种群中都表现出明显的差异，个体用来吸引配偶的视觉信号，而且关于激素（尤其是像睾酮这样的雄激素）对这些信号发展的影响，我们已经知道很多。该项目将使用最先进的半自动无线电跟踪系统，持续监测个体之间的社会互动，以检查这些互动对大脑中激素和基因表达的影响，并在该领域使用社会条件的实验操作来证明潜在的原因。将进行跨种群和跨性别的比较，使其成为首次研究女性繁殖信号的作用和调节的研究之一。总的来说，这项研究将有助于更好地理解荷尔蒙和遗传机制，使个人能够适应不断变化的社会环境。此外，这项工作将通过关键伙伴关系和当地人直接参与研究、教育推广和交流活动，在巴布亚新几内亚建立能力，这是一个生物多样性丰富的地区，具有相当大的保护问题。还将制作公共教育材料，包括介绍研究结果和研究过程的短片，以便通过经过验证和访问量很大的互联网渠道广泛传播。因此，这个项目将对自然保护和公众对科学的理解产生广泛的影响。动物行为研究议程的一个中心目标是确定雄激素和其他激素在调节装饰物表达和相关生殖行为中的作用，但迄今为止这些作用仍不清楚。有一种观点很少受到行为生态学家的关注，即雄激素是表型整合者，其作用是产生一种适应其社会环境的多维表型。这个合作项目将建立在先前对两个姐妹物种的研究基础上，这两个物种在雄性和雌性装饰上表现出种内差异，使这个系统非常适合研究这些问题。该项目由三个相互关联的研究组成，它们共同协作，将解决有关雄激素如何调节繁殖信号和相关行为表达的关键问题。首先，通过自动遥测阵列收集的高密度社会互动数据与社会环境实验操作相结合，将用于研究社会互动和早期生活条件在调节个体雄激素水平和繁殖表型中的作用。其次，结合观察、基因组和激素操作方法，将用于检查雄激素影响整个性状套房以产生综合生殖表型的程度。最后，激素植入实验和跨性别和两个密切相关物种的基因组分析将揭示调节装饰物制作和行为的激素机制的进化限制程度。通过弥合行为生态学家和内分泌学家对激素的看法之间的差距，该项目将改变我们对激素在调节表型整合和信号传导中的作用的看法。

Animals must adjust their behaviors and other traits to a constantly changing social environment. For example, the strategies and the signals that individuals use to attract mates and breed often depend on an individual's social status relative to others in the population, and that status can fluctuate as group composition changes and/or other individuals change in rank. Accordingly, the hormonal and genetic mechanisms that underlie such behaviors and signals are likely to be sensitive to social conditions. Yet, we know relatively little about these mechanisms, particularly in wild populations living under natural conditions. This project will examine the mechanisms that allow for behavioral flexibility, and the ways that those mechanisms evolve, using Australian fairy-wrens (genus Malurus) as a model system. These study species are uniquely suited to this research because they show pronounced variation, across both individuals and populations, in the visual signals that individuals use to attract mates, and a great deal is known about the effects of hormones (particularly androgens like testosterone) on the development of these signals. This project will use a state-of-the-art semi-automated radio tracking system to continuously monitor social interactions among individuals to examine the effects of those interactions on hormones and gene expression in the brain, and use experimental manipulation of social conditions in the field to demonstrate the underlying causes. Comparisons across populations and across the sexes will be conducted, making this one of the first studies to examine the role and regulation of breeding signals in females. Overall, this research will contribute to a better understanding of the hormonal and genetic mechanisms that allow individuals to adjust to a constantly changing social environment. In addition this work will build capacity in Papua New Guinea, a richly biodiverse region of considerable conservation concern, through key partnerships and direct involvement of locals in research, educational outreach, and interchange activities. Public educational materials also will be created, including short videos presenting results from the research as well as the process of doing the research, for broad dissemination through proven and highly visited internet channels. Thus, this project will have broad impacts on both conservation and public understanding of science.A central goal of the animal behavior research agenda is to identify the role of androgens and other hormones in regulating expression of ornaments and associated reproductive behaviors, yet to date these roles remain unclear. One view, which has received relatively little attention from behavioral ecologists, is that androgens are phenotypic integrators that act to produce an adaptive multi-dimensional phenotype that is well suited to its social environment. This collaborative project will build on previous research with two sister species of Malurus fairy-wren that exhibit intraspecific variation in male and female ornamentation, making this system uniquely suited for examining these issues. The project consists of three inter-related studies that, together and synergistically, will address key questions regarding how androgens modulate expression of breeding signals and associated behaviors. First, high-density data on social interactions, collected from an automated telemetry array in conjunction with experimental manipulation of social environment, will be used to examine the role of social interactions and early-life conditions in regulating individual androgen levels and breeding phenotype. Second, a combination of observational, genomic and hormone manipulation approaches will be used to examine the extent to which androgens affect whole suites of characters to produce an integrated reproductive phenotype. Finally, hormone implant experiments and genomic analyses across the sexes and across two closely related species will reveal the degree of evolutionary constraint on hormonal mechanisms regulating ornament elaboration and behavior. By bridging the gap between the ways that behavioral ecologists and endocrinologists view hormones, this project will transform the ways that we view the role of hormones in regulating phenotypic integration and signaling.