Meeting Abstract
Signal traits can convey information about an individual’s physiological state. These signals often serve an important role in social interactions – including mate choice – and thus can impact fitness. In tree swallows (Tachycineta bicolor), individuals with brighter feathers are more socially connected and more resilient under stress (Taff et. al. in prep). Little is known about the mechanisms that underlie this pattern, or the relationship between plumage color and physiological state in tree swallows. Here, we test the relationships between ventral feather brightness and several physiological measures: circulating corticosterone, oxidative stress, and blood glucose levels. Because brighter tree swallows are more stress resilient, we predict that incubating females with brighter ventral feathers will have lower levels of both baseline and stress-induced corticosterone, exhibit stronger negative feedback in the hypothalamic-pituitary-adrenal axis, and suffer from less oxidative damage. Uncovering plumage-physiology links may provide insight into candidate mechanisms linking signal traits with social interactions, performance, and fitness.
