Suliformes

Suliformes is a proposed order of birds that includes the families Sulidae (gannets and boobies), Anhingidae (anhingas), Phalacrocoracidae (cormorants), Fregatidae (frigatebirds), and Phaethontidae (tropicbirds). This grouping is based on a combination of morphological and molecular data, though its precise definition and composition have been subject to debate and reclassification over time. Historically, many of these birds were placed in the order Pelecaniformes, but genetic studies have revealed distinct evolutionary lineages, leading to the establishment of Suliformes as a separate order.

Birds within Suliformes are generally medium to large water birds. Many are marine, with species found in tropical and temperate oceans worldwide. They are often characterized by totipalmate feet, meaning all four toes are connected by webbing, though this is not universal across all proposed members. Diet typically consists of fish, squid, or crustaceans, which they obtain through diving or plunge-diving. Plumage varies but often includes dark upperparts and lighter underparts, with some species exhibiting brightly colored bare skin on their faces or throats. Nesting habits range from solitary pairs to large colonies. The relationships between the families within Suliformes are still an active area of research.