From Individuals to Communities: Consequences of Ontogenetic Functional Diversity for Community Structure and Functioning

群落生态学的一个核心挑战是理解生物多样性和生态系统功能之间的联系。群落生态学，特别是食物网理论的传统方法是基于这样一个前提，即可以通过将物种视为同质实体来进行预测。然而，没有一个种群是真正同质的，一个物种内的个体往往在其生态功能上有很大的差异。到目前为止，个体之间这种功能差异的最大来源是体型和发育阶段的差异。事实上，一个物种内不同发育阶段的功能差异往往超过了物种间的差异。尚未解决的问题是，物种内部的这种功能变化如何影响自然生态系统的结构和功能。这个问题将通过对自然池塘群落中掠食性无脊椎动物的阶段结构进行现场实验，以及发展一个新的理论框架来解释发育阶段的功能变化来回答。这些研究将首次深入了解物种在不同发育阶段的生态变化是如何改变整个生态系统的结构、动态和功能的。人类活动正在从根本上改变生态系统和自然种群。我们预测这些变化将如何影响生态系统功能的能力，将在很大程度上取决于我们对将种内多样性与生态系统功能联系起来的详细机制的理解。这项研究将使人们对决定个人如何扩大影响整个社区及其功能的机制有一个新的详细的了解。获得的结果将促进我们对是否以及哪些细节需要包括在群落动态和生态系统过程的一般预测框架中的概念理解，并指导保护和收获策略的发展，以确保重要的生态系统功能在未来不会丢失。它还将为本科生和研究生提供培训机会，包括在科学领域代表性不足的群体。

A central challenge in community ecology is to understand the connection between biodiversity and the functioning of ecosystems. The traditional approach in community ecology and particular in food web theory is based on the premise that predictions can be made by treating a species as a homogenous entity. However, no population is truly homogenous and individuals within a species often vary considerably in their ecological function. By far the largest source of this functional variation between individuals stems from differences in size and developmental stage. Indeed, the functional variation across developmental stages within a species often exceeds the variation across species. The unresolved question is how this functional variation within species affects the structure and functioning of natural ecosystems. This question will be answered using a combination of field experiments manipulating the stage-structure in predatory invertebrates in natural pond communities, and development of a new theoretical framework that accounts for functional variation across developmental stages. Together these studies will provide first insight into how the ecological variation across developmental stages within species may alter the structure, dynamics, and functioning of entire ecosystems. Human activities are fundamentally changing ecological systems and natural populations. Our ability to predict how such changes will affect the functioning of ecosystems will critically depend on our understanding of the detailed mechanisms that connect intraspecific diversity to ecosystem functions. The study will permit a new detailed understanding of the mechanisms that determine how individuals scale up to affect entire communities and their functioning. The obtained results will advance our conceptual understanding of whether and what details need to be included in a general predictive framework for community dynamics and ecosystem processes and guide the development of conservation and harvest strategies to assure that vital ecosystem functions are not lost in the future. It will also provide training opportunities for undergraduate and graduate students, including underrepresented groups in science.