What accounts for the sounds we like to hear? Is it something about the properties of our auditory systems or brains? Or are such tastes learned? Two-month-old human infants show a preference for consonant, or gentler harmonies over more dissonant or harsher ones. But it’s still impossible to know whether that preference is inborn, since the babies may have been exposed to certain sounds, even in utero. Birds show similar behaviors: they can distinguish between different kinds of sounds and certain species are attracted to certain sounds. But because no one had experimented on birds raised in a controlled, isolated environment, before they’ve experienced any social life, the reasons have remained unclear — until now.