Hormones, brain and behavior in birds: The Lehrman legacy

This short essay is based on the presentation I gave at the meeting of the Society of Behavioral Neuroendocrinology held in Tours, France in June 2023 when I received the Lehrman award for career achievement. I conducted my PhD at the Institute of Animal Behavior that was founded by Lehrman at Rutgers University. Although I never met Lehrman I was mentored by several scientists who had worked with him. I therefore decided to organize my essay about the Lehrman award around the enduring legacy of Lehrman's work as it influenced my career. Four aspects of the scientific legacy of Daniel Lehrman are distinguished and I discuss how these insights affected my own research program. A concise summary of the research I conducted in collaboration with PhD students and postdocs that relates to these topics is then presented. This research that involves several avian species includes studies of how behavior can influence the endocrine physiology and behavior of receivers of a particular signal. The cloning of the gonadotropin-releasing hormone (GnRH) gene in songbirds and analysis of the environmental factors influencing its expression demonstrated how the GnRH neuronal system is a key link between the perception of behavior and changes in endocrine physiology. Finally, there is a review of studies of the experimental analysis of the brain sites where testosterone acts to control the motivation to sing and the quality of song in songbirds that follow directly in the Lehrman line of work on how steroids regulate avian reproductive behaviors.