Penguins And Seabirds

This group gathers Birds subcategory members that spend most of their lives at sea, spanning several unrelated orders united here by that shared ocean-going habit rather than by common ancestry. It includes the penguins of the order Sphenisciformes, flightless divers whose wings have been reshaped into rigid flippers for swimming, along with a fossil relative of theirs, the giant extinct genus Icadyptes; the tube-nosed seabirds of the order Procellariiformes, the albatrosses, petrels, shearwaters and fulmars, which can glide for days over open ocean on stiff, narrow wings and locate food partly by smell, an unusual trait among birds; the order Suliformes, the cormorants, shags, gannets, boobies and frigatebirds, most of which dive or plunge for fish, while the frigatebird instead steals food in flight from other seabirds; and the pelicans, loons and grebes, freshwater and coastal divers that round out this subcategory's remaining water birds not already claimed by the wading-bird or waterfowl groups below.