Community processes structuring assembly and disassembly of bat gut-microbial communities across a gradient of habitat degradation

哺乳动物的肠道是微生物群落的家园，对个体动物的营养和健康起着重要作用。这些微生物群落或微生物组由数百种细菌组成，但存在哪种细菌以及它们有多常见，因动物个体而异。这种可变性很重要，因为异常的群体可能导致从肥胖到抑郁的各种情况。然而，微生物群落聚集或分裂的规则却知之甚少。研究人员将以野生蝙蝠为模型，研究宿主的社会性、饮食、遗传学、微生物功能和相互作用如何塑造消化微生物群的组成。这项研究的结果是了解微生物组组成的规则，有助于促进人类和野生动物的健康。为了提高学生对科学研究如何进行的理解，该团队将邀请来自全国各地的小学生参与该项目，实时分享现场数据。学生们将通过研究人员的STEM K-12计划：马来西亚蝙蝠教育冒险，学习如何分析和解释项目数据。使用现有的生物多样性模块（5-6年级）和新模块“微生物多样性：你的蝙蝠里有什么？”（6-7年级），向学生介绍微生物生态学和多样性的主题。该项目在改变学生STEM知识、技能和态度方面的成功将在干预前和干预后与对照组设计中采用定量方法进行评估。该研究将确定群落过程在跨生境退化梯度分布的食虫蝙蝠物种肠道微生物组成和功能结构中的相对作用。研究人员假设微生物群落的组装和拆卸涉及生态位过滤、物种相互作用和扩散的确定性过程。本研究将检验由生境退化引起的宿主生态变化将改变这些过程的相对影响，从而影响群落组成和功能的假设。将在马来西亚的森林改造梯度上研究蝙蝠，并为每只蝙蝠获得肠道微生物组成、宏基因组功能、饮食组成、宿主基因型和社会相互作用测量值的个体匹配样本。这些数据，结合对共发生、系统发育和功能特征模式的分析，将用于测试结构方程模型，该模型用于在因果建模框架中解开构建社区的过程。分散在构建微生物组中的作用的证据将来自社会性不同的共分布宿主物种的比较。种间关联将使用共现网络方法进行评估。功能性状空间是根据单个蝙蝠微生物组中每种细菌种型的基因组推断而开发的。利用最大似然和群落成员间的16S基因比对来估计系统发育。为了测试饮食和宿主遗传（宿主环境）在群落过程中的作用，研究人员用COI DNA条形码描述粪便中的饮食，并通过基因组指纹图谱量化宿主多样性和相关性。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Mammal guts are home to communities of microbes that play an important role in the nutrition and health of individual animals. These microbial communities, or microbiomes, are made up of hundreds of species of bacteria, but which species are present, and how common they are, varies from individual to individual animal. This variability is important because abnormal communities can lead to conditions that range from obesity to depression. However, the rules by which microbial communities come together or breakdown are poorly understood. Using wild bats as models, the researchers will investigate how host sociality, diet, genetics, and microbe functions and interactions shape the make-up of digestive microbiomes. The results of this research to understand the rules governing microbiome composition can help advance human and wildlife health. To improve students' understanding of how scientific research is conducted, the team will engage elementary school students from around the country in the project, sharing data live from the field in real time. Students will learn how to analyze and interpret the project data through the researchers' STEM K-12 initiative: The Malaysian Bat Education Adventure. Using an existing Biodiversity module (grades 5-6) and a new module "Microbial Diversity: What's in your bat?" (grades 6-7), students will be introduced to topics of microbial ecology and diversity. The program's success in changing student STEM knowledge, skills and attitude will be evaluated with quantitative methods in a pre- and post- intervention design with control group.The research will determine the relative role of community processes in structuring gut-microbial composition and function in insectivorous bat species co-distributed across a gradient of habitat degradation. The researchers hypothesize that microbiome community assembly and disassembly involve deterministic processes of niche filtering, species interactions, and dispersal. This research will test the hypothesis that changes in host ecology wrought by habitat degradation will alter the relative influence of these processes with consequences for community composition and function. Bats will be studied across a forest modification gradient in Malaysia, and individually-matched samples of gut-microbial composition, metagenome function, dietary composition, host genotype and measures of social interaction obtained for each bat. These data, in conjunction with analyses of co-occurrence, phylogenetic and functional trait patterns, will be used to test structural equation models specified to untangle the processes structuring communities in a causal modeling framework. Evidence of the role of dispersal in structuring microbiomes will derive from comparisons of co-distributed host species that differ in sociality. Interspecific associations will be assessed using co-occurrence network approaches. Functional trait space is developed from genomic inference for each bacterial phylotype within an individual bat's microbiome. Phylogenies are estimated using maximum likelihood and 16S gene alignment among community members. To test the role of diet and host genetics (the host environment) in community processes, the researchers describe diet from feces with the COI DNA barcodes, and quantify host diversity and relatedness through genome fingerprinting.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.