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2022财年的NSF生物学博士后研究奖学金，即调查基因组，环境和表型之间相互作用的生命规则的综合研究。该研究金支持研究员的研究和培训，以创新的方式为生活规则领域做出贡献。热带森林比任何其他生态系统都拥有更多的物种。不幸的是，人类活动正在减少这些森林中大型和中型动物的数量，这种现象称为动物群消失。失去这些动物会消除它们与植物和其他动物的相互作用，这意味着动物群的消失会引发热带森林功能的一系列变化。这方面的一个例子是，动物群的消失导致许多传播种子的食果动物的消失，而种子是森林再生的重要组成部分。综合来看，随着热带森林的消失而发生的变化可能会改变决定这些重要的生物多样性生态系统中植物多样性和生存动态的因素。该项目将通过在厄瓜多尔的无动物区系和完整的热带森林中进行多项实验，调查无动物区系是否、如何以及在多大程度上可能做到这一点。此外，该项目还通过对包括高中生和本科生、年轻科学家和公众在内的各种受众进行宣传、培训和指导，促进生态和保护教育。维持热带地区无与伦比的植物多样性的核心机制被认为是负密度依赖死亡率，通过这种机制，空间聚集的植物个体，特别是同种和特别是相关的个体，面临来自一系列植物敌人的高度攻击（例如，真菌病原体、昆虫和脊椎动物食草动物以及种子捕食者）。通过触发多个生态级联，动物区系破坏可能直接和间接地影响这些植物天敌的影响。例如，去动物区系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，也可能减少对抵御病原体至关重要的基因的多样性。该项目调查了动物灭绝是否改变了种子和幼苗死亡率的驱动因素，从而重塑了热带森林植物多样性的结构。这项研究比较了多个动物区系和动物区系完整的网站，并整合了实验操作（例如，排除特定植物天敌群体的处理）与基因组学一起机械地了解不同植物天敌的相对和总体优势在破坏下如何变化。该研究员将开发几个新的技能，包括在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背景的高中生合作。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估来支持。

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.