CAREER: The Metabolic Basis of Individual Variation in Behavior

Oklahoma State University, Stillwater OK

Investigators

Abstract

Individual differences in behavior set the stage for differences in the ability to find food, defend territories and attract mates, so it is important to understand what causes these differences. Variation in energy metabolism probably plays an important role because energy drives behavior, and is especially important for behaviors requiring peak performance, such as mate attraction and escaping from predators. However, the exact relationship between energy use and behavior is still poorly understood, particularly for energetically costly natural behaviors that affect fitness. To address this gap, this project will use repeated measurements of energy use and signaling behavior in a treefrog to determine how these traits relate to one another and allow these frogs to perform extremely challenging behaviors. These measurements will be made under different temperatures to determine how environmental conditions could modify the energetic costs of behavior, which could help to understand how organisms will respond to climate change. The genetic basis of the relationship between energy and behavior will be investigated to determine how these traits could evolve and potentially identify important regions of the genome affecting energetics and performance. The educational goals of this project are to build scientific capacity and knowledge, targeting middle school students’ knowledge of behavioral energetics, data interpretation skills and appreciation for the value of scientific research, as well as graduate students developing their mentorship skills. Variation in behavioral expression is often driven by variation in energetic physiology, but how these traits covary and whether they do so at the among- or within-individual level is poorly known, actively debated, and key to understanding evolutionary and ecological outcomes. The goal of this project is to identify the physiological drivers of individual variation in competitive acoustic signals in treefrogs, how physiology affects signaling plasticity in the face of environmental change, and the genetic basis of energy-signal covariance. The proposed approach is to 1) determine the energetic basis for individual variation in signaling, using repeated measurements to quantify among- and within-individual variance components in resting metabolic rate and the metabolic cost of calling, 2) test the competing predictions of different energy allocation models to determine the metabolic basis of variation in signaling plasticity, 3) discover the consequences of environmental temperature variation on behavioral energetics and its underlying individual variation and 4) use genome-wide relatedness measures to estimate heritability and the genetic covariance of these traits. Together, this project will answer fundamental questions on the mechanistic basis of individual phenotypic variation and represents a major advance in these efforts by studying a trait that is energetically costly, repeatable, and under direct sexual selection. The scientific findings from this work will be used to build a series of lesson plans aimed at teaching principles of behavioral energetics to middle school science students, and to provide a structured mentorship training program for graduate students working with undergraduate researchers. This project is jointly funded by the Behavioral Systems Cluster and the Integrative Ecological Physiology program in the Division of Integrative and Organismal Systems, and the Established Program to Stimulate Competitive Research (EPSCoR). This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.