DISSERTATION RESEARCH: Exploring convergence within pitcher plant microcosms

了解推动宿主或栖息地内群落形成的因素对全球气候变化、人类健康和微生物生态具有重要意义。随着寄主物种的迁移，其他共生体能否取代原栖息地的共生体？猪笼草有经过改造的叶子，可以收集水分和微生物，并捕获被消化的昆虫以获取营养。这些水罐可以被认为是人类肠道的植物类似物，研究它们的微生物群落是如何形成的，相互作用，并帮助宿主消化，可以帮助我们了解我们自己的肠道居民。该项目将包括为美国和马来西亚学生提供培训机会，并将促进与马来西亚婆罗洲科学家的合作和联系。研究人员将合作为马来西亚研究中心制作教育展品，并将通过哈佛自然历史博物馆的家庭项目与儿童和成年人分享猪笼草的复杂生态。形式和功能的融合在生活的所有领域都很常见，因为地理上遥远的地点类似的选择性力量塑造了进化变化。肉食性植物的猪笼草是融合进化的精妙例子：猪笼草植物的形态和功能在不同生物地理区域的三个遥远的植物谱系中分别进化。这项研究调查了与猪笼草相关的生物体在其生态相互作用的性质上是否表现出类似的趋同模式。它将比较四个不同王国的社区模式和功能，在趋同的宿主内。对于北美的猪笼草和东南亚的猪笼草两个属，不同猪笼草物种和采集点的微生物群落组成将通过真菌、细菌和原生生物的DNA测序来确定。猪笼草昆虫和微生物在一致进化的宿主上定居的能力将通过将猪笼草植物放在猪笼草的栖息地以及人工控制来调查，看看昆虫和微生物是否以及如何在陌生的宿主上定居。一项实验室实验将比较本地和一致进化的微生物群落，以促进营养有限的猪笼草从猎物中吸收氮素。最后，为了确定聚集性寄主之间的群落格局是否相似，将使用元基因组分析来检验鱼腥草和猪笼草的类群、群落格局和构成群落的因素的相似性，以通过统计和系统发育分析来检验聚集性猪笼草寄主内的群落功能能力，并使用零模型。

Understanding the factors driving community formation within a host or habitat has implications for global climate change, human health, and microbial ecology. As host species shift location, can other symbionts substitute for those from the original habitat? Pitcher plants have modified leaves that collect water and microbes, and trap insects that are digested for nutrients. These pitchers can be thought of as plant analogs to the human gut, and studying how their microbial communities form, interact with each other, and assist with host digestion could inform our understanding of our own gut inhabitants. The project will involve training opportunities for American and Malaysian students, and will foster cooperation and networking with scientists in Malaysian Borneo. The researchers will work collaboratively to create educational exhibits for the Malaysian research center, and the complex ecology of pitcher plants will be shared with children and adults through a Harvard Museum of Natural History family program.Convergence of form and function is common in all domains of life, because similar selective forces in geographically distant locations shape evolutionary change. Pitchers of carnivorous plants are exquisite examples of convergent evolution: pitcher plant morphology and function has evolved separately in three distant plant lineages in different biogeographic regions. This study investigates whether the organisms associated with pitchers show similar patterns of convergence in the nature of their ecological interactions. It will compare community pattern and function across four different kingdoms, within convergent hosts. With two genera of pitcher plants, Sarracenia in North America and Nepenthes in Southeast Asia, the microbial community composition across different pitcher plant species and collecting sites will be determined by DNA sequencing of the fungal, bacterial, and protist inhabitants. The ability of pitcher plant insects and microbes to colonize a convergently evolved host will be investigated by placing Nepenthes plants in a Sarracenia habitat, along with artificial controls, to see if and how insects and microbes colonize unfamiliar hosts. A laboratory experiment will compare native and convergently evolved microbial communities in facilitating the nutrient-limited pitcher plants in nitrogen uptake from prey. Finally, to determine if community patterns of inhabitants are similar across convergent hosts the similarity of taxa, community patterns, and factors structuring communities in Sarracenia and Nepenthes insect and microbial associates will be tested using metagenomic analyses to examine community functional capacity within convergent pitcher plant hosts by statistical and phylogenetic analyses, and with null models.