Meeting Abstract

S6-6  Tuesday, Jan. 5 11:00  Ecology muddles the relationship between hormones and life history traits DANTZER, Ben; University of Michigan dantzer@umich.edu https://sites.lsa.umich.edu/dantzerlab/

Hormones have pervasive associations with behavioral and life history traits. Despite an aim to generalize these relationships, there is often little consistency across studies or taxa. This is likely because relationships between hormones and life history traits are context-dependent and contingent upon the ecological and/or social environment. Long-term studies of wild animals living in variable environments present a unique opportunity to investigate the association between hormones and life history traits across ecological gradients. Here, I will describe the association between stress hormones (glucocorticoids) and measures of reproductive success in a long-term study of North American red squirrels (Tamiasciurus hudsonicus) in the Yukon, Canada. I will present how natural variation in food abundance, population density, and predators as well as experimental manipulation of food and density are associated with changes in glucocorticoids and reproductive success in female and male red squirrels. Overall, I will emphasize the importance of long-term field studies and how understanding the ecology of the study species can lead to a better understanding of the relationship between hormones and life history traits.