Ontogenetic transformations of selected structures and proportions in the bony labyrinth of Panthera leo and P. tigris. The y-axis refers to specific ratios, the x-axis refers to IDAS stages. Non-adult stages are represented by one specimen each, adult stages by four in P. leo and two in P. tigris; values of adult specimens are averaged (A–C). A Inner ear height against basal length in P. leo and P. tigris. Size of the radius of curvature of the semicircular canals against basal length in P. leo (B) and P. tigris (C). D Elongation of the canaliculus cochleae during ontogeny in P. leo and P. tigris. Abbreviations: ASC, anterior semicircular canal; BL, skull basal length; cco-L, length of the canaliculus cochleae; IEH, inner ear height; LSC, lateral semicircular canal; PSC, posterior semicircular canal; R, radius of curvature.