ANT LIA: Do Molecular Data Support High Endemism and Divergent Evolution of Antarctic Marine Nematodes and their Host-associated Microbiomes?

非技术摘要：南大洋长期的与世隔绝和独特的生物多样性是理解种群进化和生态的重要案例研究区域。本研究使用现代组学方法对南极海洋线虫及其寄主相关微生物群落的多样性、进化和生态学进行了评估，这些微生物群来自不同深度的不同生境。这些结果正在产生南极小型底栖动物多样性的重要基线数据集。该项目产生的所有基因组资源将作为具有长期科学再利用潜力的开源数据集向公众开放。该项目支持来自代表性不足背景的不同研究人员，并制作了一套以南极为重点的数字公共推广产品。技术摘要：线虫在世界各地的海洋沉积物栖息地中大量存在，发挥着营养循环和沉积物稳定等关键功能。然而，对这一门的研究一直存在着严重的分类缺陷，正式描述的海洋物种不到5000种。由于采样有限和南极底栖生物一般难以进入，对南大洋的动物群研究尤其不足。这项研究首次对南极东部大陆架的海洋线虫进行了大规模的分子调查，为现有的历史(形态)分类研究提供了一个重要的比较数据集。该项目使用经典分类学(显微镜)和现代组学工具相结合，以实现三个首要目标：1)确定分子数据是否支持南极底栖生态系统中底栖小型动物的高度生物多样性和特有特性；2)确定南极大陆架上起源于深海和浅水进化的海洋线虫物种的比例，并评估南大洋隐蔽物种的形成模式；3)确定与宿主相关的南极海洋线虫微生物群的最重要驱动因素。该项目的目的是迅速增进对南极小型动物进化起源的了解，深入了解关键指标属的种群水平格局，并阐明可能影响微生物群落格局的潜在生态和环境因素。更广泛的Impact活动包括一项密集的邮轮和陆基推广计划，重点是社交媒体参与和数字推广产品，提高对南极海洋生态系统和未被充分研究的微生物-动物关系的认识。多元化的研究团队包括女性科学家、第一代大学生和拉丁裔受训人员。这一奖项反映了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。

Non-technical Abstract:The long isolation and unique biodiversity of the Southern Ocean represents an important case study region for understanding the evolution and ecology of populations. This study uses modern -omics approaches to evaluate the biodiversity, evolution, and ecology of Antarctic marine nematodes and their host-associated microbiomes from a variety of habitats collected at different depths. The results are producing an important baseline dataset of Antarctic meiofaunal diversity. All genomic resources generated in this project will be publicly accessible as open-source datasets with the potential for long-term scientific reuse. This project supports diverse researchers from underrepresented backgrounds and produces a suite of Antarctic-focused digital public outreach products.Technical Abstract:Nematode worms are abundant and ubiquitous in marine sediment habitats worldwide, performing key functions such as nutrient cycling and sediment stability. However, study of this phylum suffers from a perpetual and severe taxonomic deficit, with less than 5,000 formally described marine species. Fauna from the Southern Ocean are especially poorly studied due to limited sampling and the general inaccessibility of the Antarctic benthos. This study is providing the first large-scale molecular-based investigation from marine nematodes in the Eastern Antarctic continental shelf, providing an important comparative dataset for the existing body of historical (morphological) taxonomic studies. This project uses a combination of classical taxonomy (microscopy) and modern -omics tools to achieve three overarching aims: 1) determine if molecular data supports high biodiversity and endemism of benthic meiofauna in Antarctic benthic ecosystems; 2) determine the proportion of marine nematode species that have a deep-sea versus shallow-water evolutionary origin on the Antarctic shelf, and assess patterns of cryptic speciation in the Southern Ocean; and 3) determine the most important drivers of the host-associated microbiome in Antarctic marine nematodes. This project is designed to rapidly advance knowledge of the evolutionary origins of Antarctic meiofauna, provide insight on population-level patterns within key indicator genera, and elucidate the potential ecological and environmental factors which may influence microbiome patterns. Broader Impacts activities include an intensive cruise- and land-based outreach program focusing on social media engagement and digital outreach products, raising awareness of Antarctic marine ecosystems and understudied microbial-animal relationships. The diverse research team includes female scientists, first-generation college students, and Latinx trainees.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.