Ecology and evolution of plant-animal and host-microbe mutualisms

我的研究团队研究的是互惠互利的生态和进化。大多数动物和植物至少参与了一种互惠共生；它们依赖其他物种提供营养、保护或在相互作用中传播，这些相互作用反馈给它们的伴侣，使其受益。互惠关系的著名例子包括授粉、种子传播和蚂蚁-植物共生，但互惠关系研究中增长最快的领域是与宿主相关的微生物群，这个术语指的是生活在宿主内或宿主上的所有微生物，或它们的集体基因组。这些群落中的许多微生物对宿主有益，或者至少不是致病的，但关于微生物群如何影响宿主的生理、生态和进化，仍有许多悬而未决的问题。我的研究计划试图了解互惠互利如何将相互作用的物种的命运联系在一起，影响它们的分布和丰度，特征和分子进化，甚至地球上生命的多样性。这笔赠款解决了关于不同植物-动物和宿主-微生物系统中的互惠共生、生态和进化的四个基本问题：1)互惠共生是如何在基因组水平上进化的？通过研究蚂蚁-植物和豆科植物-根瘤菌的互惠作用，我们将探索互惠的分子基础，并使用进化基因组学的方法来推断选择如何作用于编码互惠特性的基因。2)多重互惠关系如何在微观和宏观进化尺度上进化？我们将测试传粉者和蚂蚁互助者是否对田间共同花园中的热带植物施加非加性选择，并收集多个植物-动物和植物-微生物互惠的全球数据集，以探索它们如何在植物系统发育中同步进化。3)我们能预测不同微生物群和环境的宿主受益吗？我们正在开发一个使用微小水生植物Lemna Minor及其微生物群的高通量实验系统，我们将测试宿主-微生物相互作用在许多不同的微生物群落和许多多元环境中的结果。4)哪个‘第二基因组’具有更持久的跨代影响：微生物组还是表观基因组？我们将使用我们的新系统在有压力和良性的环境中培养宿主种群，并实验性地操纵微生物区系和表观遗传标记，测量宿主表型和世代适应性。我们将确定微生物组和表观基因组对跨代可塑性的相对重要性，特别是在应对压力时。这项研究将通过对具有高度生态或基因组复杂性的真实世界系统的研究，显著提高我们对互惠关系如何进化的理解。它还将为HQP提供广泛的培训，他们将学习进行严格的实验室和现场实验，并获得分子和计算生物学方面的需求技能。这种综合的方法鼓励HQP的智力发展，并将为他们在基础科学或应用科学领域的职业生涯做好准备。

My research team studies the ecology and evolution of mutualism. Most animals and plants are involved in at least one mutualism; they depend on other species for nutrition, protection, or dispersal in interactions that feed back to benefit to their partners. Well-known examples of mutualism include pollination, seed dispersal, and ant-plant symbioses, but the fastest growing area of mutualism research is the host-associated microbiome, a term that refers either to all the microbes living together in or on a host, or their collective genomes. Many microbes in these communities are beneficial to hosts, or at least not pathogenic, but there are many open questions about how microbiomes affect host physiology, ecology, and evolution. My research program seeks to understand how mutualism links the fates of interacting species, affecting their distribution and abundance, trait and molecular evolution, and even the diversification of life on Earth. This grant addresses four fundamental questions about mutualism ecology and evolution in diverse plant-animal and host-microbe systems: 1) How does mutualism evolve at a genomic level? Studying ant-plant and legume-rhizobium mutualisms, we will explore mutualism's molecular basis and use approaches from evolutionary genomics to infer how selection acts on genes that encode mutualistic traits. 2) How do multiple mutualisms evolve at micro- and macro-evolutionary scales? We will test whether pollinators and ant mutualists exert non-additive selection on a tropical plant in field common garden and assemble a global dataset of multiple plant-animal and plant-microbe mutualisms to explore how they evolve in tandem across the plant phylogeny. 3) Can we predict host benefits across microbiomes and environments? We are developing a high-throughput experimental system using the tiny aquatic plant Lemna minor and its microbiota, and we will test the outcome of host-microbe interactions across many distinct microbial communities and in many multivariate environments. 4) Which 'second genome' has more persistent transgenerational effects: the microbiome or the epigenome? We will use our new system from 3) to grow host populations in stressful and benign environments and experimentally manipulate microbiota and epigenetic marks, measuring host phenotypes and fitness across generations. We will determine the relative importance of the microbiome and the epigenome to transgenerational plasticity, especially in response to stress. This research will significantly improve our understanding of how mutualisms evolve through studies of real-world systems with high ecological or genomic complexity. It will also provide broad training to HQP who will learn to conduct rigorous lab and field experiments and acquire in-demand skills in molecular and computational biology. This integrative approach encourages the intellectual development of HQP and will prepare them for careers in basic or applied science.