Collaborative Research: BEE: Impacts of abiotic environment, pathogen resistance and Pre-Columbian human management on Neotropical canopy palm abundances

在热带雨林中，密切相关的树种在当地的丰富度可能会有几个数量级的差异，这为我们提供了一个引人注目的背景，让我们重新审视生态学的一个核心主题：为什么有些物种极其常见，而另一些物种却非常稀有？这个项目试图在南美树冠棕榈树中回答这个问题，南美树冠棕榈树是一个多样化的群体，包括几个地理上分布广泛的物种，这些物种对人类的有用程度和丰度模式都不同。这项研究试图量化生态、进化和人为过程对棕榈树丰度的相对和综合影响。这项研究有望通过整合不同学科的观点来推进科学知识，以实现对人类、生态和进化影响如何相互作用以塑造生物系统的更全面的理解。该项目具有重要的社会和经济影响，因为棕榈树为全球数百万人提供了食物、收入和基本需求的物质。在该项目期间制作的教育电影和教学模块预计将被美国数千名高中生和大学生使用。研究生和本科生、博士后研究员和高中教师将接受培训。这项研究采用多尺度抽样设计，将当地的生态和微进化过程与景观丰度模式联系起来，以检验两个主要假设：1)通过抗性基因(R基因)的有效防御使普通物种能够逃避负密度依赖；2)过去数千年来的人类管理促进了有用物种的丰富。这是通过将当代基因组分析与航空成像和机器学习相结合来实现的，这些机器学习能够识别和绘制大片地区的个别树冠树。定期普查提供了与当地物种丰度有关的成虫和苗木存活的信息，苗圃实验将进一步探索R基因多样性和苗木存活之间的关系。该项目还测试了前哥伦布时代人类对当代树木种群的潜在影响，方法是对土壤岩心进行古生态采样，包括木炭和植硅体采样，同时考虑非生物环境。这种方法预计将阐明负密度依赖、非生物环境和哥伦布之前的人类管理的相对和综合影响，所有这些都被认为在某种程度上影响了丰度，但通常被孤立对待。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。

In tropical rainforests, local abundances of closely related tree species can vary by several orders of magnitude, providing a compelling context in which to revisit a core theme in ecology: why is it that some species are extremely common, while others are rare? This project seeks to answer this question in South American canopy palm trees, a diverse group that includes several geographically widespread species that vary in degree of usefulness to humans and in patterns of abundance. The research seeks to quantify the relative and combined influences of ecological, evolutionary, and anthropogenic processes on palm abundances. The research is expected to advance scientific knowledge by integrating perspectives from separate disciplines to achieve a more synthetic understanding of how human, ecological, and evolutionary impacts interact to shape biotic systems. The project has important societal and economic implications because palms provide food, income, and material for basic needs for millions of humans around the globe. Educational films and teaching modules produced during the project are expected to be used by thousands of high school and college students in the United States. Graduate and undergraduate students, post-doctoral fellows, and high school teachers will receive training.The research employs a multi-scale sampling design to link local ecological and microevolutionary processes to landscape patterns of abundance to test two major hypotheses: 1) that effective defenses via resistance genes (R genes) give common species the ability to escape negative density dependence, and 2) that human management over the past several millennia has promoted the abundances of useful species. This is achieved by combining contemporary genomic analysis and aerial imaging and machine learning capable of identifying and mapping individual canopy trees over vast areas. Regular censuses provide information on survival of adults and seedlings of focal species in relation to local abundances, and a nursery experiment will further explore relationships between R gene diversity and seedling survival. The project also tests potential impacts of Pre-Columbian humans on contemporary tree populations using paleo-ecological sampling of soil cores, including charcoal and phytolith sampling, while accounting for abiotic environment. This approach is expected to shed light on the relative and combined impacts of negative density dependence, abiotic environment, and Pre-Columbian human management, all thought to influence abundance in some way but typically treated in isolation.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.