Complex social behaviors are regulated by the social decision-making network. The neural nodes underlying this network are generally conserved across species. However, activation of these neural nodes can result in markedly different social or mating displays. Our goal is to understand differences in how steroid hormones (e.g., testosterone) activate the social decision-making network and contribute to differences in complex social behavioral traits across species. More recently, we have focused on how high-impact social signals (drumming in woodpeckers) are supported by neurophysiological adaptations.