Water bird

However, this classification has been disputed, and sometimes the hummingbirds are raised to their own order, trochiliformes, instead of a family.

Another major group are the core water birds that may or may not include the tropic birds, sunbittern and kegu.

They do, however, include the loons, albatrosses, petrels, storks, boobies, cormorants, pelicans, herons, ibises, and penguins, whose grouping has been supported by numerous phylogenetic studies.

Of these, the penguins, order Sphinisiformes, are perhaps the most charismatic and familiar, noted for their extreme adaptation to marine life.

Though some extinct forms grew to be about the size of humans, the largest extant species is the emperor penguin, and the smallest is the little blue penguin.

In addition to their unique morphologies, many species are noted for their massive aggregations, extreme parental care, and social behaviors.

In contrast to the core water birds are the core land birds, or taluraves.

They include many of the most widely recognized large predatory birds, such as the Old World vultures of order Cathartiformes, and the hawks, eagles, kites, and New World vultures of order Axiptripoformes, members of which are large diurnal birds with sharply hooked beaks, long broad wings, and strong legs.