Fig. 3
From: Vocal tract anatomy of king penguins: morphological traits of two-voiced sound production
General anatomical structure of the king penguin vocal tract. a: Photograph of a male adult king penguin with a schematic drawing of the vocal tract to illustrate its location in the body. b: Image of the entire vocal tract of a male king penguin including beak, upper respiratory tract, trachea, syrinx, lower respiratory tract with main bronchi and lungs. White box indicates the position of the bronchial type syrinx. (R = right, L = left)