EAGER: Community and physiological ecology: Linking consumer homeostatic physiology and behavior to plant community dynamics

Southern Illinois University At Carbondale, Carbondale IL

Investigators

Abstract

An important focus of ecology is understanding how the interplay between the environment and organisms shape ecosystems. For example, some studies have explored how changes in temperature and rainfall influence the types of animals and plants found within an area. Other studies have explored how organisms may shape their environment by building structures, or changing the chemistry or rate of nutrient processing within an environment. This study will directly link how environmental changes may influence broader ecological patterns through their effects on the physiology of animals. More specifically, this study examines how changes in the environment directly influence the internal physiology of small grassland rodents and how this physiological stress influences their foraging behavior which in turn influences the types of plants found in their habitats. New technologies will be employed to record and manipulate the internal stress levels experienced by rodents in the field and to track how this stress influences their movement, foraging and feeding patterns. This research is important in developing a general understanding of how organism physiology and behavior scale up to shape ecosystem properties. This study will also inform conservation efforts by allowing land managers to develop strategies that may reduce the negative effects of environmental change on the physiology of animals. This project will support the research training of undergraduate and graduate students and will provide opportunities for K-12 students and teachers. The integration of animal homeostatic function into the field of ecology is essential for characterizing and forecasting the responses of communities to changing environmental conditions. Changes in the homeostatic function of animals may, for example, play an important role in structuring the form and function of ecosystems through shifts in animal physiology and behavior that influence predator-prey interactions, levels of competition and rates of nutrient cycling. Capitalizing on recent advances in radio-telemetry and physiological manipulation techniques, this study will experimentally alter the stress hormone and water physiology of granivorous kangaroo rats to track associated shifts in their foraging behavior and habitat use. By applying stable isotopes to flowering plants commonly consumed by these rodents, this study will close the loop between the physiological response of consumers to environmental stressors and its potential to alter seed dispersal and germination patterns. Integration of these disparate approaches will demonstrate a new community (physiological) ecology framework that may shift long-held research paradigms. This ecological framework will provide new opportunities for researchers to explore and test how diverse homeostatic processes (e.g. thermoregulation, ecoimmunology, and nutrient stoichiometry) mediate community function and structure across a variety of ecosystems.