Ear Formation

Around 8 weeks gestation, the outer ear starts as a groove on the neck, just below the mouth. Over the next two weeks, the outer ear migrates to its final position and becomes shell shaped.¹ From there, the outer ear forms more folds, reaching a more mature shape by 20 weeks.² The ear’s shape helps a person localize sounds; and since every ear shape is slightly different, everyone’s brain has made slightly different connections so that people have trouble telling the direction of sounds that are recorded inside someone else’s ear.³ Oddly enough, the outer ear actually continues to grow for a person’s entire life.⁴