All data logarithmically transformed using the natural logarithm (ln). A, total labyrinth volume over body mass; B, total length of labyrinth over body mass; C, volume of cochlea over body mass; D, length of canaliculus cochleae for aqueduct of cochlea over body mass; E, length of bony channel for aqueduct of vestibule over body mass; F, length of cochlear canal over body mass; G, length of slender portion of anterior semicircular canal over body mass; H, length of slender portion of lateral semicircular canal over body mass; I, length of slender portion of posterior semicircular canal over body mass; J, arc radius of curvature of anterior semicircular canal over body mass; K, arc radius of curvature of lateral semicircular canal over body mass; L, arc radius of curvature of posterior semicircular canal over body mass. The outlier that falls well below regression line in G-L is Tursiops truncatus.