The Science of Parrot Hearing: What You’re Seeing in Aura and Mojo’s Ears Parrots have one of the most efficient hearing systems in the bird world, even though they don’t have external ears like mammals. What you see on the side of their head—those small oval openings under the feathers—are direct pathways to a highly specialised auditory system. Parrots locate sound with impressive accuracy. Even without an outer ear structure, they detect tiny timing and volume differences between each ear. Th