Imperium naturæ C. Linnaeus, 1758 - nature
   Mundus Plinius - physical world
     naturalia - natural bodies
       Regnum Animale C. Linnaeus, 1758 - animal kingdom see Kingdom Animalia Linnaeus, 1758
         Class Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758
           Order Anseres Linnaeus, 1758 see Suborder Anseres Linnaeus, 1758
             Genus Colymbus Linnaeus, 1758
               1 Colymbus arcticus Linnaeus, 1758 see Gavia arctica (Linnaeus, 1758)
               2 Colymbus cristatus Linnaeus, 1758 see Podiceps cristatus (Linnaeus, 1758)
               3 Colymbus auritus Linnaeus, 1758 see Podiceps auritus (Linnaeus, 1758)
               4 Colymbus podiceps Linnaeus, 1758 see Podilymbus podiceps (Linnaeus, 1758)