Oral Paper

         Phytochemical

Quantifying chemodiversity as a way of understanding the ecological function of phytochemicals

Presenting Author
Hampus Petrén
Description
Plants produce a great variety of phytochemical compounds, which are important for shaping interactions between the plants and their biotic and abiotic environment. Traditionally, research has often focused on examining the function of individual compounds on specific ecological interactions, such as herbivory and pollination. However, phytochemicals occur in multicompound mixtures that form a complex phenotype, and relatively little is known about what aspects of this phenotype are most important for its function. Recently, measuring chemodiversity has attracted considerable interest as an ecologically meaningful way to quantify mixtures of phytochemical compounds. However, our understanding about how such diversity, and what components of it, are important for function has remained limited. In this talk, I go through the theoretical background of how the diversity of compounds could be linked to function, and examine evidence for such effects in the literature. Then, I introduce the R package chemodiv, which provides functions for calculating and visualizing chemical diversity, with methods that take the richness, relative abundance and – most importantly – structural and/or biosynthetic dissimilarity of compounds into account. With such new comprehensive measures, chemodiversity can be measured in ways that are suitable for different kinds of datasets and questions. We believe that these theoretical and statistical developments will increase our knowledge of how phytochemicals and their diversity varies across different levels of biological organization, and how they affect ecological interactions between plants and other organisms.