(RUI) From Complex Environments to Underlying Mechanisms: A Network Approach to Multi-trait Tradeoffs

为了生存和生存，生物体必须获得食物，能够繁殖，避免被吃掉，并防止感染。然而，这些重要特征中的每一个都需要花费高昂的维护费用，这可能会导致这些特征之间的权衡。也就是说，对一种特征的投资是以另一种特征为代价的。研究人员提出了一种实验方法，检查三个重要的生物特征(例如，免疫、繁殖和身体运动)之间的同时权衡，这将为深入了解多性状权衡在塑造动物生存方式中的作用提供依据。考虑到性状权衡受环境的影响，这些研究将在模拟北美环境变化动态的一系列操纵环境中进行。在压力大的情况下，对一种特质的投资可能会优先于对另一种特质的投资。然而，如果个体遇到有利的环境(例如，无限制地获得食物)，可能会保持繁殖和免疫力等两个特征，这表明权衡可能取决于食物的可获得性。食品供应的影响往往受到其他环境因素的影响，这些因素可能伴随着食品供应的减少(例如热浪)，食品供应和温度之间的相互作用可能会对权衡产生深远的影响。这项研究将首次使用网络分析方法来表征环境变异性和动物生活史策略之间的相互作用。这种方法已被证明是研究各种现象的强大工具，如社会互动、互联网的结构，以及优化工程问题的解决方案。这项研究的大部分将由来自代表性不足的少数群体的学生完成，并将由一个旨在教育社区成员(特别是K-8年级的学生)了解昆虫生物学重要性的科学推广计划来补充。拟议的研究将使用操纵性方法，在翼型二态田间板球比赛中，检查在三个广泛重要的生活史特征：生殖、免疫功能和运动方面的投资之间的权衡。所得经验数据将用于网络分析方法，通过确定几个网络度量(例如，连通性、介入性和模块化)来表征这些特征之间的动态关系。他们还将检查生活史网络和潜在生理特征网络(例如，抗氧化防御和代谢率)之间的联系。此外，他们将使用网络方法来确定两个普遍的环境约束(食物可获得性和温度)在多性状权衡和性状-性状相互作用中的独立和交互作用。因此，拟议的研究将使用一种综合的方法来更好地理解复杂的特征系统是如何发展和维持的。它将对包括生态免疫学、生态生理学、网络分析和生活史进化在内的多个生物学学科产生影响。研究人员将为学生提供广泛的研究培训，其中许多学生来自代表该地区和佐治亚南方大学(GSU)学生群体的服务不足的少数群体。为了实现他们的研究目标，他们将开发一个旨在教育年轻人了解昆虫的外展项目，昆虫是一个重要的分类学群体。他们将在格拉斯哥州立大学博物馆创建一个网站和一个附带的外展，提供当地昆虫的信息。他们还将构建和传播一个旨在满足佐治亚州教育部绩效标准的教育模块；其中将包含结构化活动、信息讲义和现场蟋蟀，供K-8年级的学生用来培养科学素养。

To survive and persist, an organism must acquire food, be able to reproduce, avoid being eaten, and prevent infection. However, each of these important traits is costly to maintain, which can lead to tradeoffs among the traits. That is, investment into one trait comes at a cost to another. The researchers propose an experimental approach examining simultaneous tradeoffs among three important biological traits (e.g., immunity, reproduction, and body movement) that will provide insight into the role of multi-trait tradeoffs in shaping how animals survive. Given that trait tradeoffs are influenced by the environment, these studies will occur in a range of manipulated environments that simulate the dynamics of environmental change in North America. Under stressful conditions, investment into one trait can take precedence over investment into another trait. However, if individuals encounter favorable environments (e.g., unlimited access to food), two traits, such as reproduction and immunity, may be maintained, suggesting that tradeoffs may be dependent upon food availability. The effects of food availability are often influenced by other environmental factors that may accompany reduced food availability (e.g., heat waves), and interactions between food availability and temperature may profoundly influence tradeoffs. This research will be the first to characterize the interplay between environmental variability and animal life history strategies using a network analysis approach. This approach has proven to be a powerful tool for studying diverse phenomena, such as social interactions, the structure of the Internet, and for optimizing solutions to engineering problems. Much of this research will be performed by students from under-represented minority groups, and it will be complemented by a science outreach program designed to educate community members (particularly K-8 students) on the importance of insect biology.The proposed research will use a manipulative approach in a wing-dimorphic field cricket to examine tradeoffs among investment into three life history traits of widespread importance: reproduction, immune function, and locomotion. Resultant empirical data will be used for a network analysis approach to characterize dynamic relationships among these traits through the determination of several network metrics (e.g., connectivity, betweenness, and modularity). They will also examine linkages between the life history networks and a network of underlying physiological traits (e.g., antioxidant defense and metabolic rate). Further, they will use a network approach to determine the independent and interactive role of two universal environmental constraints (food availability and temperature) in multi-trait tradeoffs and trait-trait interactions. Thus, the proposed study will use an integrative approach to better understand how complex trait systems develop and are maintained. It will have impact on multiple biological disciplines, including ecological immunology, ecological physiology, network analyses, and life history evolution. The researchers will provide extensive research training to students, many of whom come from under-served minority groups representative of both the region and the student body at Georgia Southern University (GSU). To complement their research goals, they will develop an outreach program designed to educate young people about insects, an important taxonomic group. They will create a website and an accompanying outreach exhibition at the GSU Museum that provides information about local insects. They will also construct and disseminate an educational module designed to meet the State of Georgia's Department of Education performance standards; this will contain structured activities, informational handouts, and live crickets that K-8 students can use to develop scientific literacy.