Becky Ripley and Emily Knight find out what it takes to learn the language of your people, with the help of some extremely chatty little birds. The song of the zebra finch has been compared to a 90's dial-up modem running triple-speed, or an alien fax machine. But to a female zebra finch, it's a song of irresistible seduction. The males learn their song in a very similar way to the way we learn language, and it all starts with the babies. Through babbling, then copying, then innovating motifs of their own, the zebra finches take their language and then put their own distinctive stamp on it. But if they don't learn it at just the right time, as a chick, they can't learn it as an adult. How does human language acquisition work, and what would happen if you denied a baby the opportunity to learn to speak? The surprising answer takes us to 1970s Nicaragua, and the extraordinary story of the birth of a language... Produced by Becky Ripley and Emily Knight. Featuring Professor Ofer Tchernichovski from Hunter College at CUNY, and Dr Judy Shepard-Kegl from the University of Southern Maine.