Hormonally-regulated trade-offs: Evolutionary variability and phenotypic plasticity in testosterone signaling pathways

Abstract

Hormones have been proposed as internal signals that mediate life history trade-offs in both invertebrates and vertebrates. This chapter reviews the evidence for such a role. It outlines possible endocrine pathways by which such hormones could mediate life history trade-offs, focusing on sex steroids in vertebrates, and discusses evolutionary scenarios that may account for interspecific variation in hormonally regulated life-history trade-offs. Throughout, it attempts to outline future research directions.