Kari Norman, University of California, Berkeley

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Understanding the impact of anthropogenic change and natural disturbance on ecological process is a fundamental goal of ecology. However, understanding of large-scale change patterns is severely limited by the fine-scale data necessary to directly measure process. Biodiversity metrics such as species diversity have long been used as a surrogate for community structure in broad-scale studies, with the implicit assumption that 1) species diversity is a good indicator of community change; and 2) species diversity is linked to ecological process. While the second point is still contested, recent work demonstrates that species diversity does not capture the kinds of changes happening in communities today. Due to the increasing availability of functional trait data, functional diversity metrics provide a powerful alternative for assessing community change on a broad scale. By directly summarizing the traits that confer ecological process, these metrics provide a mechanistic look at community response to perturbation.

We develop a framework to leverage existing databases of occurrence time series paired with species-level trait data to address three main questions: 1) Has functional diversity changed significantly across time? 2) Are there patterns of functional diversity response across disturbance types? 3) Does functional diversity give a different picture of global biodiversity change than species-based counterparts? Using a case study from the BioTime and EltonTraits databases, we will discuss the necessity for greater ecological detail in understanding biodiversity change and the challenges associated with adapting functional trait concepts to large-scale analyses.

Abstract Author(s): Kari Norman, Carl Boettiger