Testing Structure/Function Relationships in an Ecological Context: Integration of Biomechanics, Behavior and Performance during Aerial Predation in Dragonflies

Harvard University, Cambridge MA

Investigators

Abstract

PROJECT TITLE: Testing structure/function relationships in an ecological context: Integration of biomechanics, behavior and performance during aerial predation in dragonflies PRINCIPAL INVESTIGATOR: Stacey Anne Combes PROJECT NUMBER: IOS 0952471 In order to understand the diversity of animal body forms found in nature, as well as the potential application of particular features to man-made devices, it is essential to first clarify the relationship between a given structure and the function(s) for which it has evolved. In studies of animal locomotion, this relationship has typically been examined in the context of a single, isolated function that is easy to elicit and measure, such as forward locomotion at a steady speed, without any clear indication of how important this function is for animals in the wild. A more complete understanding of the role of particular body structures can be gained by examining their effect on performance during complex, demanding locomotory behaviors that are known to affect an animal's survival or reproductive success. The current study will demonstrate this approach through integrated analyses of the biomechanics, behavior and performance of dragonflies hunting aerial prey. Studies will be conducted in a novel, outdoor artificial dragonfly habitat, in which natural predatory behaviors can be elicited reliably from known individuals, and filmed with a high-speed multi-camera system to reconstruct three-dimensional body motions. This will be the first project to explore the mechanical determinants of aerial predation, one of the most challenging and complex behaviors performed by flying animals. Through a series of manipulations, the work will provide a better understanding of the effects of body mass distribution, wing flexibility, and wing damage on flight performance. In addition, the project will train several undergraduate and high school students in basic experimental and field techniques, while providing data on prey capture rates and the effectiveness of wild dragonflies in controlling mosquito populations.