In lizards, enhancer activity was in the ear canal, which suggests that elastic cartilage had begun migrating from the gills ...

elastic cartilage is very flexible and found in the external ear, voice box, and tube between the ear and throat; and fibrocartilage is tough and absorbs impacts at the joints and in the spine.

Have you ever wondered why our ears look the way they do? That soft, curved shape we rarely think twice about might actually ...