Fowl are birds belonging to one of two biological orders, namely the gamefowl or landfowl (Galliformes) and the waterfowl (Anseriformes). Anatomical and molecular similarities suggest these two groups are close evolutionary relatives; together, they form the fowl clade which is scientifically known as Galloanserae or Galloanseres. This clade is also supported by morphological and DNA sequence data as well as retrotransposon presence/absence data.
Galliformes is an order of heavy-bodied ground-feeding birds that includes turkeys, chickens, quail, and other landfowl. Gallinaceous birds, as they are called, are important in their ecosystems as seed dispersers and predators, and are often reared by humans for their meat and eggs, or hunted as game birds.
The hoatzin or hoactzin is a species of tropical bird found in swamps, riparian forests, and mangroves of the Amazon and the Orinoco basins in South America. It is the only extant species in the genus Opisthocomus which is the only extant genus in the Opisthocomidae family under the order of Opisthocomiformes. Despite being the subject of intense debate by specialists, the taxonomic position of this family is still far from clear.
Vegavis is a genus of extinct bird that lived in Antarctica during the Maastrichtian stage of the Late Cretaceous, around 66.5 million years ago. The type species is Vegavis iaai. Vegavis was considered to be a member of Anseriformes within Galloanserae, but this claim has not been supported by recent studies.
Ichthyornis is an extinct genus of toothy seabird-like ornithuran from the late Cretaceous period of North America. Its fossil remains are known from the chalks of Alberta, Alabama, Kansas, New Mexico, Saskatchewan, and Texas, in strata that were laid down in the Western Interior Seaway during the Turonian through Campanian ages, about 95–83.5 million years ago. Ichthyornis is a common component of the Niobrara Formation fauna, and numerous specimens have been found.
Dromornithidae, known as mihirungs and informally as thunder birds or demon ducks, were a clade of large, flightless Australian birds of the Oligocene through Pleistocene epochs. All are now extinct. They were long classified in Struthioniformes, but are now usually classified as galloanseres. Dromornithids were part of the Australian megafauna. One species, Dromornis stirtoni, was 3 m tall. Only a single species, Genyornis newtoni survived into the Late Pleistocene. They are thought to have been herbivorous.
The Portezuelo Formation is a geologic formation of Late Cretaceous age, outcropping in the Mendoza, Río Negro and Neuquén provinces of Argentina. It is the fourth-oldest formation in the Neuquén Group and the older of the two formations in the Río Neuquén Subgroup. Formerly, that subgroup was treated as a formation, and the Portezuelo Formation was known as the Portezuelo Member.
Ichthyornithes is an extinct group of toothed avialan dinosaurs very closely related to the common ancestor of all modern birds. They are known from fossil remains found throughout the late Cretaceous period of North America, though only two genera, Ichthyornis and Janavis, are represented by complete enough fossils to have been named. Ichthyornitheans became extinct at the Cretaceous–Paleogene boundary, along with enantiornitheans, all other non-avian dinosaurs, and many other animal and plant groups.
John Alan Feduccia is a paleornithologist specializing in the origins and phylogeny of birds. He is S. K. Heninger Distinguished Professor Emeritus at the University of North Carolina. Feduccia's authored works include three major books, The Age of Birds, The Origin and Evolution of Birds, and Riddle of the Feathered Dragons.
Gastornithiformes were an extinct order of giant flightless fowl with fossils found in North America, Eurasia, possibly Australia. Members of Gastornithidae were long considered to be a part of the order Gruiformes. However, the traditional concept of Gruiformes has since been shown to be polyphyletic.
Apatornis is a genus of ornithuran dinosaurs endemic to North America during the late Cretaceous. It currently contains a single species, Apatornis celer, which lived around the Santonian-Campanian boundary, dated to about 83.5 million years ago. The remains of this species were found in the Smoky Hill Chalk of the Niobrara Formation in Kansas, United States. It is known from a single fossil specimen: a synsacrum, the fused series of vertebrae over the hips.
Limenavis is a genus of ornithuran dinosaurs from the Late Cretaceous. It lived about 70 million years ago, around the Campanian-Maastrichtian boundary. Known from several broken bones, the remains of the only known species Limenavis patagonica were found in rocks of the "lower member" of the Allen Formation at Salitral Moreno, 20 km south of General Roca, Río Negro (Argentina). It is one of the closest relatives, in the fossil record, of the modern birds.
Graculavus is a prehistoric bird genus that was described in the 19th century by American paleontologist O. C. Marsh. Its remains were found in the Late Cretaceous Austin Chalk of Texas, USA, and Lance Formation, and the controversial Hornerstown Formation which straddles the Cretaceous–Paleocene boundary, possibly dating to the Danian stage. These birds lived on the shores of the northwestern Atlantic and the Western Interior Seaway some 68 to 62 million years ago.
Vegaviidae is an extinct family of ornithurine dinosaurs of uncertain phylogenetic placement, which existed during the Late Cretaceous and possibly the Paleocene. Fossils attributed to the family have been found in Canada, Chile, New Zealand, and Antarctica.
The year 2018 in archosaur paleontology was eventful. Archosaurs include the only living dinosaur group — birds — and the reptile crocodilians, plus all extinct dinosaurs, extinct crocodilian relatives, and pterosaurs. Archosaur palaeontology is the scientific study of those animals, especially as they existed before the Holocene Epoch began about 11,700 years ago. The year 2018 in paleontology included various significant developments regarding archosaurs.
Asteriornis is an extinct genus of bird from the Late Cretaceous of Belgium which is known from a single species, Asteriornis maastrichtensis. It was closely related to birds of the extant superorder Galloanserae such as chickens and ducks. Members of the genus were small, long-legged birds that lived near the coastline and co-existed with more "primitive" types of birds such as Ichthyornis. Asteriornis is one of the oldest-known birds irrefutably belonging to the group Neornithes, which encompasses all modern birds. It possesses characteristics of both galliformes and anseriformes, indicating its position as a close relative of the last common ancestor for both groups.
Austinornis is an extinct genus of prehistoric bird of uncertain phylogenetic placement from the Late Cretaceous of Texas. The paleontologist Julia A. Clarke named the genus in 2004 based on a partial tarsometatarsus fossil from Austin Chalk. Although Austinornis was thought to be a pangalliform, other researchers have disputed its classification and dismissed it in phylogenetic analyses due to the fragmentary nature of the holotype. Notably, in 2014, Gerald Mayr suggested that Austinornis is a non-neornithine from the Coniacian or Santonian age and that the specimen probably belongs to the ornithurine Apatornis or Iaceornis.
Tonsala is an extinct genus of Plotopteridae, a family of flightless seabird similar in biology with penguins, but more closely related to modern cormorants. The genus is known from terrains dated from the Late Oligocene of the State of Washington and Japan.
Waltonavis is an extinct genus of potentially leptosomiform bird from the Early Eocene London Clay Formation of Essex, United Kingdom. The genus contains two species: W. paraleptosomus and W. danielsi, both known from partial skeletons.
