How are complex, learned behaviors—like speech and singing—encoded in our genes, and how did they evolve? Human speech depends on our ability to learn and control vocalizations, a process not well understood at the molecular level. This ability is rare in the animal kingdom and is absent in our closest primate relatives and common laboratory rodents. To explore the neural and genetic bases of vocal learning, I conducted comparative experiments with over 50 avian species. This research involved developing new computational analysis pipelines and adapting lab practices for field studies, significantly enhancing our understanding of gene expression and regulation in birds. Ultimately, these findings investigate three potential mechanisms for the evolution of a brain circuit that controls complex sensorimotor tasks.