Systema naturæ - nature
   Universum - universe see [unranked] Mundus Plinius
     naturalia - natural bodies
       Regnum Animale nom. inval. - animal kingdom see Kingdom Animalia Linnaeus, 1758
         Class Aves Plinius, nom. inval. - birds see Class Aves Linnaeus, 1758
           Order Gallinae nom. inval. see Order Gallinae Linnaeus, 1758
             Genus Otis nom. inval. see Genus Otis Linnaeus, 1758
               Tarda nom. inval.