Where does music come from? What kind of agency does a song have? What is at the root of musical pleasure? Can music die? These are some of the questions the Greeks and the Romans asked about music, song, and the soundscape within which they lived, and that this book examines. Focusing on mythical narratives of metamorphosis, it investigates the aesthetic and ontological questions raised by fantastic stories of musical origins. Each chapter opens with an ancient text devoted to a musical metamorphosis (of a girl into a bird, a nymph into an echo, men into cicadas, etc.) and reads that text as a meditation on an aesthetic and ontological question, in dialogue with 'contemporary' debates - contemporary with debates in the Greco-Roman culture that gave rise to the story, and with modern debates in the posthumanities about what it means to be a human animal enmeshed in a musicking environment.