NSF Postdoctoral Fellowship in Biology: Are the Consequences of Wildlife Extirpation in Tropical Forests Reshaping the Drivers of Plant Mortality?

该行动资助了美国国家科学基金会2022财年生物学博士后研究奖学金，研究基因组，环境和表型之间相互作用的生命规则的综合研究。该奖学金支持将以创新方式为《生活规则》领域作出贡献的研究员的研究和培训。热带森林比任何其他生态系统拥有更多的物种。不幸的是，人类活动正在减少这些森林中大中型动物的数量，这种现象被称为退化。失去这些动物会消除它们与植物和其他动物的相互作用，这意味着退化会引发热带森林功能的一连串变化。其中一个例子是，退化导致许多以水果为食的动物消失，这些动物传播种子，而种子是森林再生的重要组成部分。总的来说，热带森林退化所发生的变化可能会改变这些重要的生物多样性生态系统中决定植物多样性和生存动态的因素。该项目将通过在厄瓜多尔毁损和完好的热带森林中设置的多项实验，调查毁损是否、如何以及在多大程度上可能造成这种情况。此外，该项目还通过向包括高中生和本科生、青年科学家和公众在内的不同受众进行宣传、培训和指导，促进生态和保护教育。在热带地区，维持植物多样性的主要机制被认为是负密度依赖性死亡率，通过这种机制，空间上聚集的植物个体，特别是同种和相关的个体，面临着一系列植物敌人（如真菌病原体、昆虫和脊椎动物食草动物以及种子捕食者）的攻击。通过触发多重生态级联，毁损可以直接或间接地影响这些植物敌人的影响。例如，退化的一个后果是种子传播服务减少，导致植物遗传多样性降低，这也可能减少对增强抵御病原体的重要基因的多样性。该项目调查了退化是否改变了种子和幼苗死亡的驱动因素，从而重塑了热带森林中植物多样性的结构。本研究比较了多个退化和动物群完整的位点，并将实验操作（例如，排除特定植物敌人群体的处理）与基因组学相结合，以机械地了解不同植物敌人在退化下的相对和总体优势如何变化。该研究员将发展一些新技能，包括基因组学和生物信息学的能力。更广泛的影响包括通过科学实习和研讨会与当地少数族裔高中学生合作。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。

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2022, Integrative Research Investigating the Rules of Life Governing Interactions Between Genomes, Environment and Phenotypes. The fellowship supports research and training of the Fellow that will contribute to the area of Rules of Life in innovative ways. Tropical forests hold more species than any other ecosystem. Unfortunately, human activities are reducing the number of large- and medium-sized animals in these forests, a phenomenon called defaunation. Losing these animals eliminates their interactions with plants and other animals, which means that defaunation can trigger a cascade of changes in how tropical forests are functioning. One example of this is that defaunation leads to the loss of many fruit-eating animals that disperse seeds, an important part of forest regeneration. When taken together, changes that are occurring as tropical forests become defaunated may alter factors determining the diversity and survival dynamics of plants in these important and biodiverse ecosystems. This project will investigate if, how, and to what extent defaunation may be doing this through multiple experiments set up in defaunated and intact tropical forests in Ecuador. Further, this project facilitates ecological and conservation education through outreach, training, and mentoring to diverse audiences that include high school and undergraduate students, young scientists, and members of the public.The central mechanism maintaining the unmatched plant diversity in the tropics is thought to be negative density-dependent mortality, by which spatially aggregated plant individuals, particularly conspecific and especially related individuals, face heightened attacks from a suite of plant-enemies (e.g., fungal pathogens, insect and vertebrate herbivores, and seed predators). By triggering multiple ecological cascades, defaunation may directly and indirectly affect the impacts these plant enemies have. For example, one consequence of defaunation is decreased seed dispersal services resulting in lower plant genetic diversity, potentially also reducing the diversity of genes important for mounting defenses against pathogens. This project investigates if defaunation alters the drivers of seed and seedling mortality, thereby reshaping what structures plant diversity in tropical forests. This research compares multiple defaunated and faunally-intact sites and integrates experimental manipulations (e.g., treatments that exclude specific groups of plant enemies) with genomics to mechanistically understand how the relative and overall strengths of different plant enemies change under defaunation. The Fellow will develop several new skills including competence in genomics and bioinformatics. Broader impacts include working with local high school students from minority backgrounds through science internships and workshops.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.