COLLABORATIVE RESEARCH: Understanding how a Hormone-signaling Pathway Modulates Behavioral Phenotype within a Social Network

社交网络是大多数动物社会的共同特征。虽然我们知道合作或攻击等行为的个体差异会影响个体在其社会网络中扮演的角色，但我们对这些差异背后的生理机制知之甚少。由于雄性形成的合作伙伴关系是复杂社会网络的基础，因此，线尾侏儒猴为研究激素、行为和社会网络之间的联系提供了一个模型系统。利用这一模型系统，本研究将整合进化、行为、内分泌和神经遗传学方法，以了解合作中个体差异的生理和进化基础，以及这些个体层面的过程如何以动态的方式影响个体在其社会网络中的角色和地位。由于内分泌功能在许多动物中都是相似的，因此这项工作的结果将广泛适用。该项目将在美国和厄瓜多尔实地培训至少16名本科生和1名研究生进行综合研究。这项研究也将在国家动物园亚马逊科学画廊的一个计划展览中展出，该展览将描述社会行为的荷尔蒙基础，并强调人类和动物社会网络之间的相似性。研究成果将被纳入在厄瓜多尔主持这项工作的蒂蓬蒂生物多样性站的热带生态学课程。本项目由动物行为计划和国际科学与工程联合资助。该项目将把激素调节网络和社会网络联系起来，以改变我们对内分泌系统如何在个人和群体层面上调节行为和影响社会动态的理解。该项目将测试两种关于选择如何塑造激素介导的社会行为进化的假设，包括睾酮：表型整合假说和表型独立假说，在线尾侏儒猴中，雄性合作在一条腿上进行交配展示。这个高度整合的项目将量化男性在自然界中的行为（优势、合作、展示率），使用纳米标签和接近数据记录器捕捉所有的社会互动并绘制社会网络，测量全年循环激素水平，使用GnRH挑战描述不同地位男性睾酮生产的最大能力，测量社会入侵对激素滴度的影响，阻断或增加激素滴度以操纵表型。并使用RT-qPCR测量这些雄性大脑中类固醇生成酶、类固醇受体和类固醇影响肽信号系统的候选基因的表达水平。然后将这些来自单个鸟类的数据结合起来，使用二元和加权模型来检查网络结构，并检查激素对网络结构和动态的影响。该研究的所有数据将存档在史密森尼候鸟中心的网站上（http://www.si.edu/smbc）。线尾侏儒猴的脑转录组组装将被发布在NCBI GenBank上。

Social networks are a common characteristic of most animal societies. While we know that individual differences in behaviors such as cooperation or aggression influence the role that individuals play within their social network, we know little about the physiological mechanisms underlying those differences. Wire-tailed manakins provide a model system to study the links between hormones, behavior and social networking because males form cooperative partnerships that are the foundation of complex social networks. Using this model system this research will integrate evolutionary, behavioral, endocrine and neurogenetic approaches to understand the physiological and evolutionary basis of individual variation in cooperation and how those individual-level processes scale up to influence an individual's role and position within their social network in a dynamic fashion. Because endocrine function is similar across a wide variety of animals, the outcomes of this work will be broadly applicable. The project will train at least 16 undergraduate students and 1 graduate student in integrative research in the US and at the field site in Ecuador. This research will also be featured in a planned exhibit which will describe the hormonal basis of social behavior and highlight the similarities between human and animal social networks at the National Zoological Park's Amazonia Science Gallery. Research products will be integrated in to tropical ecology courses at the Tipunti Biodiversity Station which hosts the work in Ecuador. This project is jointly supported by the Animal Behavior Program and International Science and Engineering.This project will link hormone-regulatory networks and social networks to transform our understanding of how the endocrine system regulates behavior and influences social dynamics at the individual and population levels. The project will test two alternative hypotheses for how selection has shaped the evolution of hormone-mediated social behaviors involving testosterone: the phenotypic integration hypothesis and the phenotypic independence hypothesis in wire-tailed manakins where males cooperate to perform mating displays on a lek. This highly integrative project will quantify male behaviors in nature (dominance, cooperation, display rate), use nanotags and proximity data loggers to capture all the social interactions and map the social network, measure circulating hormone levels across the year, describe the maximum capacity for testosterone production in males of different status using GnRH challenges, measure the effect of social intrusion on hormone titers, block or increase hormone titers to manipulate phenotype, and measure expression levels of candidate genes for steroidogenic enzymes, steroid receptors and steroid influenced peptide signaling systems in the brains of these males using RT-qPCR. These data from individual birds will then be combined to examine network structures using binary and weighted models and to examine the influence of hormones on network structure and dynamics. All data from the study will be archived at the Smithsonian Migratory Bird Center web site (http://www.si.edu/smbc). The brain transcriptome assembly for the wire-tailed manakin will be posted on NCBI GenBank.