Warlaumont and colleagues reviewed recent research about how infants’ vocal productions and auditory experiences are organized over a day, with implications for development. Everyday vocalizations appear to be clustered hierarchically in time (e.g., there is more difference in vocalization quantity from one hour to the next hour than from one 5-min interval to the next). Vocalizations also appear to be a type of exploratory foraging for social responses, with patterns of vocal exploration changing as children develop. Regarding the sounds infants encounter, different musical frequencies may foster learning about category generalization. Robert Goldstone of the Percepts and Concepts Laboratory at Indiana University and editor of the APS journal Current Directions in Psychological Science interviews Anne Warlaumont, Professor in the Department of Communication at University of California, Los Angeles.