Birdsong Learning: Evolutionary, Behavioral, and Hormonal Issues

Birdsong is a complex vocal signal that functions in a reproductive context to attract mates and defend territories. It is of interest to neuroscientists because it is a complex motor behavior that is learned via a developmental process that involves the precise guiding of motor patterns by auditory feedback. Song learning includes a sensory phase, when an auditory memory is formed, and this memory is used as a template for the later sensorimotor phase of development. There is substantial species variation in this learning process that may have been shaped by natural selection to optimize behavioral complexity and plasticity. Steroid hormones such as estradiol may promote song memory formation, and androgens close the sensorimotor phase and induce the crystallization of adult species-typical song.