Meeting Abstract
Endocrine systems are by definition dynamic and flexible, characterized by carefully regulated circulating ligands that control changes in physiology, development, and behavior across altered intrinsic or extrinsic conditions. Glucocorticoids are thought to be an important coping mechanism for vertebrates facing changes in their environments, as these hormones promote adaptive responses following both predictable and unpredictable environmental perturbations. Glucocorticoid plasticity – the ability of one individual to alter circulating glucocorticoids or other components of the hypothalamic-pituitary-adrenal-axis (HPA-axis) across a gradient of environmental conditions – is thought to be central to the ability of organisms to cope with rapid changes in our dynamic world. The HPA-axis and circulating glucocorticoid concentrations represent complex traits, however, and this complexity needs to be explicitly incorporated into future work on glucocorticoid plasticity. I will outline different types of glucocorticoid plasticity and review previous work on the topic. I will discuss statistical tools which can enable us to quantify individual variation in glucocorticoid plasticity as well as explore the fitness consequences of this variation. Finally, I will discuss the implications of variation in endocrine plasticity for predicting coping ability within and across populations and species.
