Collaborative Research: The interplay between host diet, immunity, reproduction, and the microbiome across an anthropogenic-disturbed landscape

最近有证据表明，动物消化道内的微生物不仅对消化很重要，而且还影响整体健康。动物体内有数以万亿计的微生物，然而，拥有这些微生物中的大多数会带来什么影响尚不清楚。到目前为止所知的主要集中在微生物对消化的重要性上。然而，目前的研究表明，动物的微生物的影响远远超出肠道，影响免疫系统，甚至压力。该项目旨在了解这些微生物对通过生态旅游暴露于变化和非自然饮食的濒危鬣蜥自由生活种群的健康和生存的重要性。该项目将测试不断变化的微生物群落和关键生理参数与自然种群的繁殖和生存之间的关系。此外，在实验室中，研究人员将通过实验测试饮食、压力和微生物的变化如何影响健康和生理，以了解是什么导致野生鬣蜥观察到的变化。将生理和微生物变化与自然界中动物种群的波动联系起来，将是向前迈出的创新一步。最后，了解这些相互作用的发生和方向将为人类诱导的饮食变化对野生动物的影响提供重要的见解，并提供关于受威胁物种亟需的生物学知识。最近的许多研究在模型系统中确定了微生物群和宿主健康之间的重要联系。然而，微生物组和对健康和生存至关重要的生理功能之间的机械联系大多仍未被探索。此外，由于进化史是微生物组组成的主要决定因素之一，缺乏分类广度严重限制了对宿主栖息地、饮食和免疫与微生物组组成和后基因组功能之间的生理联系的理解。调查自由生活动物体内微生物群落和与健康相关的指标的研究也很少。因此，目前关于这些关系的知识缺乏重要的生态学相关性，也缺乏对环境变化对内生微生物群落的影响的了解。为了解决目前的知识差距，该项目将研究自然和圈养环境中的鬣蜥，以测试生态免疫指数、基于人为的饮食变化以及巴哈马群岛支离破碎的岛屿景观中微生物群之间的关系。在实验室中，主要研究人员将在圈养鬣蜥中进行与生态相关的实验操作，以测试野生种群的方向关系。主要调查人员还将结合长期标记重新捕获数据集(37年以上)来调查这些协会随时间的稳定性，以评估生态免疫、氧化和微生物群指数对暴露在不同人类影响下的不同人群的生殖产出和生存的影响。该奖项由生物科学理事会内的综合组织系统部门、环境生物学部门和生命风险基金规则共同资助。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

It has recently become evident that microbes within the digestive tract of an animal are not only important for digestion but also influence overall health. An animal lives with trillions of microorganisms in its body, yet the implications of having most of these microorganisms are unknown. What is known thus far is focused primarily on the importance of microorganisms for digestion. However, current work suggests that an animal's microbes have effects that extend far beyond the gut, impacting the immune system and even stress. This project seeks to understand the importance of these microorganisms for health and survival in free-living populations of endangered iguanas that are exposed to changing and unnatural diets via ecotourism. The project will test how changing microbial communities and key physiological parameters relate to reproduction and survival in natural populations. Additionally, in the laboratory the researchers will experimentally test how changes in diet, stress, and microbes affect health and physiology in order to understand what is causing the observed changes in wild iguanas. Connecting physiological and microbial changes with animal population fluctuations in nature will be an innovative step forward. Finally, understanding both the occurrence and direction of these interactions will provide important insights into the effects of human-induced diet shifts on wildlife and much needed biological knowledge regarding threatened species.Many recent studies have identified significant connections between the microbiome and host health in model systems. However, mechanistic links between the microbiome and physiological functions that are key to health and survival remain mostly unexplored. Furthermore, given that evolutionary history is one of the primary determinants of microbiome composition, the lack of taxonomic breadth severely restricts understanding of the physiological link between host habitat, diet, and immunity with microbiome composition and metagenomic function. There is also a paucity of research investigating microbial communities and health-related metrics within free-living animals. Thus, current knowledge of these relationships lacks critical ecological relevance and an understanding of the impact of environmental changes on endo-microbial communities. To address these current knowledge gaps, the project will study iguanas in both natural and captive settings, in order to test relationships among ecoimmune indices, anthropogenic-based diet changes, and the microbiome across a fragmented, insular landscape in The Bahamas. In the laboratory, the principal investigators will perform ecologically-relevant experimental manipulations in captive iguanas to test directional relationships in wild populations. The principal investigators will also investigate the stability of these associations over time in conjunction with a long-term mark recapture data set (37+ years) to estimate the influence of ecoimmunological, oxidative, and microbiome indices on reproductive output and survival across different populations exposed to variable human influence.This award was co-funded by the Division of Integrative Organismal Systems, the Division of Environmental Biology, and the Rules of Life Venture Fund within The Directorate for Biological Sciences.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.