Dimensions: Costs and benefits of chronic viral infections in natural ecosystems

这项研究项目将调查关于病毒如何控制微生物群落结构和功能的新假说。对病毒的传统看法是，它们会对受感染宿主的健康状况产生负面影响。换句话说，它们被严格地视为病原体，宿主试图清除病毒。该项目将探索另一种假设：慢性病毒感染对宿主健康有积极贡献，通过保护宿主免受更多致病病毒的感染，增加病毒-宿主对的成功。在这种模式下，许多病毒提供的竞争优势对维持微生物生物多样性起着直接作用。黄石国家公园温泉中的微生物群落将被用来验证这一假设：i)将病毒丰度和多样性的时间变化与宿主遗传和分类多样性联系起来；ii)识别慢性病毒，并在实验室量化慢性病毒感染的适合性后果；iii)在实验室和现场实验中评估去除病毒的影响；以及iv)开发包括慢性感染的成本和收益的宿主-病毒相互作用的理论和计算模型。预计这项研究将为病毒不仅影响微生物生物多样性，而且影响植物和动物的生物多样性提供新的见解。这项研究将具有广泛的科学意义。众所周知，微生物在地球上的生命中扮演着重要的角色，包括作为地球食物网的基础，影响碳和氮循环，以及对人类健康的影响。病毒感染所有形式的生命，包括微生物。这项研究将揭示病毒如何影响生态系统的组成和功能。该研究项目还将利用黄石国家公园作为一个极具吸引力和引人注目的场所，吸引K-12年级的教师、学生和公众参与生物多样性科学，以吸引公众对科学的兴趣。研究人员将为K-12科学教师创建实地课程，从黄石到K-12学校的虚拟教室，在线课程和研讨会，以及专注于黄石微生物研究的全国播放的电影。该项目的结果有望揭示关于地球上生物多样性的基本新知识。

This research project will investigate a new hypothesis about how viruses may control the structure and function of microbial communities. The traditional view of viruses is that they negatively impact the fitness of infected hosts. In other words, they are viewed strictly as pathogens, in which the host tries to eliminate the virus. This project will explore an alternative hypothesis: that chronic viral infections contribute positively to host fitness, increasing the success of the virus-host pair by protecting their hosts from infection by even more pathogenic viruses. Under this model, the competitive advantage provided by many viruses plays a direct role in maintaining microbial biodiversity. Microbial communities in hot springs in Yellowstone National Park will be used to test this hypothesis by: i) linking temporal changes in virus abundance and diversity to host genetic and taxonomic diversity, ii) identifying chronic viruses, and quantifying the fitness consequences of chronic viral infections in the laboratory, iii) assessing the effects of removing viruses in laboratory and field experiments, and iv) developing a theoretical and computational model of host-viral interactions that includes the costs and benefits of chronic infections. It is anticipated that this research will provide new insights into how viruses influence not only microbial biodiversity, but also the biodiversity of plants and animals. This research will be of broad scientific importance. It is known that microbes play a significant role in life on earth, including as the foundation for earth's food webs, influencing carbon and nitrogen cycles, and in human health. Viruses infect all forms of life, including microbes. This study will reveal more about how viruses impact the composition and function of ecosystems. The research project also will engage K-12 teachers, students, and the public on the science of biodiversity using Yellowstone National Park as a highly attractive and visible venue for public interest in science. The investigators will create field courses for K-12 science teachers, virtual classrooms from Yellowstone to K-12 schools, online courses and workshops, and nationally aired films focused on microbial research in Yellowstone. Results from this project are expected to reveal fundamental new knowledge about the biodiversity of life on earth.