Pelecaniformes

The Pelecaniformes are an order of medium-sized and large waterbirds found worldwide. As traditionally defined, they encompass all birds that have feet with all four toes webbed. Hence, they were formerly also known by such names as totipalmates or steganopods. Under this obsolete definition, the Fregatidae (frigatebirds), Sulidae, Phalacrocoracidae, Anhingidae (darters), and Phaethontidae (tropicbirds) were included in the Pelecaniformes. Subsequent molecular and morphological studies indicate they are in fact not close relatives to "true" Pelecaniformes, and they are now placed in their own orders, Suliformes and Phaethontiformes, respectively.

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