Penguins are a group of aquatic flightless birds. They live almost exclusively in the Southern Hemisphere, with only one species, the Galápagos penguin, found north of the Equator. Highly adapted for life in the water, penguins have countershaded dark and white plumage and flippers for swimming. Most penguins feed on krill, fish, squid and other forms of sea life which they catch while swimming underwater. They spend roughly half of their lives on land and the other half in the sea.
The mesites (Mesitornithidae) are a family of birds that are part of a clade (Columbimorphae) that include Columbiformes and Pterocliformes. They are smallish flightless or near flightless birds endemic to Madagascar. They are the only family with more than two species in which every species is threatened.
The Procolophonia are a suborder of herbivorous reptiles that lived from the Middle Permian till the end of the Triassic period. They were originally included as a suborder of the Cotylosauria but are now considered a clade of Parareptilia. They are closely related to other generally lizard-like Permian reptiles such as the Millerettidae, Bolosauridae, Acleistorhinidae, and Lanthanosuchidae, all of which are included under the Anapsida or "Parareptiles".
The Phaethontiformes are an order of birds. They contain one extant family, the tropicbirds (Phaethontidae), and one extinct family Prophaethontidae from the early Cenozoic. Several fossil genera have been described.
Neoaves is a clade that consists of all modern birds with the exception of Paleognathae and Galloanserae. Almost 95% of the roughly 10,000 known species of modern birds belong to the Neoaves.
Aequornithes, or core water birds are defined as "the least inclusive clade containing Gaviidae and Phalacrocoracidae".
Cariamiformes is an order of primarily flightless birds that has existed for over 60 million years. The group includes the family Cariamidae (seriemas) and the extinct families Phorusrhacidae, Bathornithidae, Idiornithidae and Ameghinornithidae. Though traditionally considered a suborder within Gruiformes, both morphological and genetic studies show that it belongs to a separate group of birds, Australaves, whose other living members are Falconidae, Psittaciformes and Passeriformes.
Eufalconimorphae is a proposed clade of birds, consisting of passerines, parrots, falcons, caracaras, and forest falcons. It has whole-genome DNA support. The Eufalconimorphae is noted to produce aerodynamic force during the upstroke of flight to help create a vertical flight pattern.
Australaves is a recently defined clade of birds, consisting of the Eufalconimorphae as well as the Cariamiformes. They appear to be the sister group of Afroaves. As in the case of Afroaves, the most basal clades have predatory extant members, suggesting this was the ancestral lifestyle; however, some researchers like Darren Naish are skeptical of this assessment, since some extinct representatives such as the herbivorous Strigogyps led other lifestyles. Basal parrots and falcons are at any rate vaguely crow-like and probably omnivorous.
Afroaves is a clade of birds, consisting of the kingfishers and kin (Coraciiformes), woodpeckers and kin (Piciformes), hornbills and kin (Bucerotiformes), trogons (Trogoniformes), cuckoo roller (Leptosomiformes), mousebirds (Coliiformes), owls (Strigiformes), raptors (Accipitriformes) and New World vultures (Cathartiformes). The most basal clades are predatory, suggesting the last common ancestor of Afroaves was also a predatory bird.
Telluraves is a recently defined clade of birds defined by their arboreality. Based on most recent genetic studies, the clade unites a variety of bird groups, including the australavians as well as the afroavians. They appear to be the sister group of a newly defined clade centered on Aequornithes.
Columbea is a clade suggested by genome analysis that contains Columbiformes, Pteroclidae (sandgrouse), Mesitornithidae (mesites) and Mirandornithes. Until their recent placement as the sister taxon to Passerea, in the last decade various genetic analysis found them to be in clade Metaves.
Gruimorphae is a clade of birds that contains the orders Charadriiformes and Gruiformes identified by molecular analysis. This grouping has had historical support, as various charadriiform families such as the families Pedionomidae and Turnicidae were classified as gruiforms.
Eurypygimorphae or Phaethontimorphae is a clade of birds that contains the orders Phaethontiformes (tropicbirds) and Eurypygiformes recovered by genome analysis. The relationship was first identified in 2013 based on their nuclear genes. Historically these birds were placed at different parts of the tree, with tropicbirds in Pelecaniformes and the kagu and sunbittern in Gruiformes. Some genetic analyses have placed the eurypygimorph taxa in the controversial and obsolete clade Metaves, with uncertain placement within that group. More recent molecular studies support their grouping together in Eurypygimorphae, which is usually recovered as the sister taxon to Aequornithes within Ardeae.
The Otidimorphae is a clade of birds that contains the orders Cuculiformes (cuckoos), Musophagiformes (turacos), and Otidiformes (bustards) identified in 2014 by genome analysis. While the bustards seem to be related to the turacos, other genetic studies have found the cuckoos to be closer to the bustards than the turacos are.
Ardeae is a clade of birds that contains Eurypygimorphae and Aequornithes, named in 2014 by genome analysis. Members of Eurypygimorphae were originally classified in the obsolete group Metaves, and Aequornithes were classified as the sister taxon to Musophagiformes or Gruiformes.
Picocoraciae is a clade that contains the order Bucerotiformes and the clade Picodynastornithes supported by various genetic analysis and morphological studies. While these studies supported a sister grouping of Coraciiformes and Piciformes, a large scale, sparse supermatrix has suggested alternative sister relationship between Bucerotiformes and Piciformes instead.
Columbimorphae is a clade discovered by genome analysis that includes birds of the orders Columbiformes, Pterocliformes (sandgrouse), and Mesitornithiformes (mesites). Previous analyses had also recovered this grouping, although the exact relationships differed. Some studies indicated a sister relationship between sandgrouse and pigeons while other studies favored a sister grouping of mesites and sandgrouse instead.
Picodynastornithes is a clade that contains the orders Coraciiformes and Piciformes. This grouping also has current and historical support from molecular and morphological studies.
