1) Animal order 2) Order colymbiformes 3) Order podicipediformes 4) Order podicipitiformes 5) Podicipediformes 6) Podicipitiformes 1) Podicipediformes 2) Podicipitiformes 
Colymbiformes is a disused order of birds that was once used to classify grebes and loons. Scientific study has revealed that these two types of waterbirds are not so closely related; they have been reclassified in the orders Podicipediformes and Gaviiformes, respectively. ...
former taxonomic order that included the water birds known as loons and grebes. Later scholarship determined that these two groups were not related, ...