NSF Award
1456492
The question of why some individuals are better at coping with stress than others is fundamental and pressing. Identifying the causes of differences in the stress response requires understanding how the stress response varies within and across populations, and how these differences affect survival and reproduction. Organisms respond to a diversity of stressors through behavior and physiology, and this response is important for coping with immediate threats, yet it can also impose substantial damage. Stress resilience is the rapid and effective termination of the stress response and may be an important predictor of the capacity to persist in changing environments. This research will address how stress responsiveness and stress resilience affects fitness across a range of environments. The results of these experiments could significantly advance understanding of the traits that drive vulnerability to stressors and adverse health outcomes, and help to predict the potential for individuals, populations, and species to persist in a changing environment. This research will be integrated with education and outreach in several ways. A partnership with the Cornell Lab of Ornithology's education program will produce accessible and engaging multimedia pieces on how organisms, including modern humans, cope with stress. These materials will be designed to enhance public interest in science, and to provide a standards-based resource for use in secondary schools and undergraduate biology courses nationwide. The research team is also collaborating with local environmental groups and researchers at each study site to develop field-based public outreach programs.<br/><br/>The researchers engaged in this collaborative project will experimentally manipulate phenotype and exposure to stressors in a widely distributed songbird, the tree swallow (Tachycineta bicolor), to determine whether variation in specific components of the stress response are causally linked to behavior, phenotypic damage, gene expression, and fitness. Novel techniques that enable the manipulation of the hormonal stress response in free-living and freely-behaving birds will be coupled with advances in remote monitoring and tracking to reveal the detailed behavioral changes and fitness effects of variation in the hormonal stress response. The potential for selection to shape the efficacy of negative feedback will be assessed by estimating the heritability and consistency of trait expression within and across seasons. Coordinated experiments across four populations that breed in differing environments from Alaska to Tennessee will address how variation in specific components of the stress response influence the ability to survive and reproduce in the presence of stressors. The data obtained through this project will be stored in databases maintained by the Principal Investigator and collaborators, and archived through the Cornell eCommons facility. Data will be provided as supplementary material to publications, and made publicly available within five years of the conclusion of the project.
