Gallornis
Encyclopedia
| name = Gallornis
| fossil_range = Early Cretaceous
Early Cretaceous
The Early Cretaceous or the Lower Cretaceous , is the earlier or lower of the two major divisions of the Cretaceous...

,
| display parents = 3
| parent_authority = Lambrecht, 1931
| genus = Gallornis
| species = straeleni
| parent_authority = Lambrecht, 1931
| authority = Lambrecht, 1931
}}

Gallornis is a genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of prehistoric bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...

s from the Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

. The single known species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 Gallornis straeleni lived near today's Auxerre
Auxerre
Auxerre is a commune in the Bourgogne region in north-central France, between Paris and Dijon. It is the capital of the Yonne department.Auxerre's population today is about 45,000...

 in Yonne
Yonne
Yonne is a French department named after the Yonne River. It is one of the four constituent departments of Burgundy in eastern France and its prefecture is Auxerre. Its official number is 89....

 département (France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

); it has been dated very tentatively to the Berriasian
Berriasian
In the geological timescale, the Berriasian is an age or stage of the Early or Lower Creteceous. It is the oldest or lowest subdivision in the entire Cretaceous. It spanned between 145.5 ± 4.0 Ma and 140.2 ± 3.0 Ma...

-Hauterivian
Hauterivian
The Hauterivian is, in the geologic timescale, an age in the Early Cretaceous epoch or a stage in the Lower Cretaceous series. It spans the time between 136.4 ± 2 Ma and 130 ± 1.5 Ma...

 stages, that is about 140-130 million years ago.. The known fossil material consists of a worn partial femur
Femur
The femur , or thigh bone, is the most proximal bone of the leg in tetrapod vertebrates capable of walking or jumping, such as most land mammals, birds, many reptiles such as lizards, and amphibians such as frogs. In vertebrates with four legs such as dogs and horses, the femur is found only in...

 and a fragment of the humerus
Humerus
The humerus is a long bone in the arm or forelimb that runs from the shoulder to the elbow....

.

This is a highly significant taxon
Taxon
|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...

 for theories about the evolution
Evolution
Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...

 of birds. Unfortunately, it is not known from much or well-preserved material. It has been proposed that the remains show features only known from the Neornithes - the group of birds that exists today. Thus, the Gallornis fossils suggest that as early as about 130 million years ago or more the ancestors of all living birds might already have been an evolutionary lineage distinct from the closely related Hesperornithes
Hesperornithes
Hesperornithes is an extinct and highly specialized clade of Cretaceous toothed birds. Hesperornithine birds, apparently limited to former aquatic habitats in the Northern Hemisphere, include genera such as Hesperornis, Parahesperornis, Baptornis, Enaliornis, and probably Potamornis, all...

 and Ichthyornithes (essentially modern birds retaining some more ancient features like teeth) and the more distantly related Enantiornithes
Enantiornithes
Enantiornithes is an extinct group of primitive birds. They were the most abundant and diverse avialans of the Mesozoic. Almost all retained teeth and clawed fingers on each wing, but otherwise looked much like modern birds externally. Over 50 species of Enantiornithines have been named, but some...

 (a group of more primitive toothed birds which were the most successful avians in the Mesozoic
Mesozoic
The Mesozoic era is an interval of geological time from about 250 million years ago to about 65 million years ago. It is often referred to as the age of reptiles because reptiles, namely dinosaurs, were the dominant terrestrial and marine vertebrates of the time...

).

Ecology

During the time of Gallornis, its range was located around 30°N, north of the Tropic of Cancer
Tropic of Cancer
The Tropic of Cancer, also referred to as the Northern tropic, is the circle of latitude on the Earth that marks the most northerly position at which the Sun may appear directly overhead at its zenith...

 arid
Arid
A region is said to be arid when it is characterized by a severe lack of available water, to the extent of hindering or even preventing the growth and development of plant and animal life...

ity belt. However, the Cretaceous was a hot and humid age in general, so the habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...

 might have more resembled West Africa
West Africa
West Africa or Western Africa is the westernmost region of the African continent. Geopolitically, the UN definition of Western Africa includes the following 16 countries and an area of approximately 5 million square km:-Flags of West Africa:...

 around the Gulf of Guinea
Gulf of Guinea
The Gulf of Guinea is the northeasternmost part of the tropical Atlantic Ocean between Cape Lopez in Gabon, north and west to Cape Palmas in Liberia. The intersection of the Equator and Prime Meridian is in the gulf....

. Higher sealevels had large parts of Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

 submerged for much of the time, and Southeast Europe
Southeast Europe
Southeast Europe or Southeastern Europe is a relatively recent political designation for the states of the Balkans. Writers such as Maria Todorova and Vesna Goldsworthy have suggested the use of the term Southeastern Europe to replace the word Balkans for the region, to minimize potential...

 and Asia Minor
Asia Minor
Asia Minor is a geographical location at the westernmost protrusion of Asia, also called Anatolia, and corresponds to the western two thirds of the Asian part of Turkey...

 had not even attached to that continent yet (see also Haţeg Island
Hateg Island
Hațeg Island was a large offshore island in the Tethys Sea during the Cretaceous period. It was situated in an area corresponding to the region around modern-day Hațeg, Romania...

, Haţeg Basin). The Alpide orogeny (the uplift of the Eurasia
Eurasia
Eurasia is a continent or supercontinent comprising the traditional continents of Europe and Asia ; covering about 52,990,000 km2 or about 10.6% of the Earth's surface located primarily in the eastern and northern hemispheres...

n latitudinal mountain belt) had not even gotten underway.

Gallornis was a contemporary of many (non-avian
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...

) dinosaur
Dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...

s living around the (Second) Tethys Sea. In the archipelago
Archipelago
An archipelago , sometimes called an island group, is a chain or cluster of islands. The word archipelago is derived from the Greek ἄρχι- – arkhi- and πέλαγος – pélagos through the Italian arcipelago...

 that was then Europe, huge sauropods appear to have been the dominant herbivore
Herbivore
Herbivores are organisms that are anatomically and physiologically adapted to eat plant-based foods. Herbivory is a form of consumption in which an organism principally eats autotrophs such as plants, algae and photosynthesizing bacteria. More generally, organisms that feed on autotrophs in...

s. Apart from some early birds, pterosaur
Pterosaur
Pterosaurs were flying reptiles of the clade or order Pterosauria. They existed from the late Triassic to the end of the Cretaceous Period . Pterosaurs are the earliest vertebrates known to have evolved powered flight...

s roamed the skies of the European microcontinents (more abundant and diverse than the few birds), while semi-aquatic and fin
Fin
A fin is a surface used for stability and/or to produce lift and thrust or to steer while traveling in water, air, or other fluid media, . The first use of the word was for the limbs of fish, but has been extended to include other animal limbs and man-made devices...

ned marine crocodilia
Crocodilia
Crocodilia is an order of large reptiles that appeared about 84 million years ago in the late Cretaceous Period . They are the closest living relatives of birds, as the two groups are the only known survivors of the Archosauria...

ns were common. Stegosaurs were apparently rare and might have been Huayangosauridae. Heterodontosauridae
Heterodontosauridae
Heterodontosauridae is a family of early ornithischian dinosaurs that were likely among the most basal members of the group...

 like Echinodon
Echinodon
Echinodon meaning "hedgehog tooth" in reference to the spines on its teeth , occasionally known as Saurechinodon, is a genus of small European dinosaur of the early Cretaceous Period , 140 million years ago.-Discovery and species:The type specimen was discovered by Samuel Beckles in the Purbeck...

may have been contemporaries of this early bird. The giant teleosaurid Machimosaurus
Machimosaurus
Machimosaurus is an extinct genus of teleosaurid crocodyliform from the Late Jurassic and Early Cretaceous . The type species, Machimosaurus hugii, was found in France. Other fossils have been found in Austria, England, Germany, Portugal and Switzerland...

, which grew to 9 meters (30 feet) also must have lived here as a major predator. Theropods like Concavenator
Concavenator
Concavenator is a genus of theropod dinosaur that lived approximately 130 million years ago during the early Cretaceous period . The type species is C. corcovatus; Concavenator corcovatus means "hump backed hunter from Cuenca"...

, Nuthetes
Nuthetes
Nuthetes is the name given to a dubious, possibly dromaeosaurid, genus of theropod dinosaur, known only from fossil teeth and jaw fragments found in rocks of the middle Berriasian age in the Cherty Freshwater Member of the Lulworth Formation in England...

and Baryonyx
Baryonyx
Baryonyx is a genus of carnivorous saurischian dinosaur first discovered in clay pits just south of Dorking, England, and later reported from fossils found in northern Spain and Portugal. It is known to contain only one species, Baryonyx walkeri...

may have existed alongside it as well.

Classification

As it is so close to the common origin of all living birds, Gallornis cannot be assigned to any living family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 and probably not even to any extant order
Order (biology)
In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...

. It was allied with the Paleocene
Paleocene
The Paleocene or Palaeocene, the "early recent", is a geologic epoch that lasted from about . It is the first epoch of the Palaeogene Period in the modern Cenozoic Era...

 Scaniornis
Scaniornis
Scaniornis is a prehistoric bird genus. The only species, Scaniornis lundgreni, lived in the MP 1-5 ....

, a probable waterbird that is sometimes allied with flamingo
Flamingo
Flamingos or flamingoes are gregarious wading birds in the genus Phoenicopterus , the only genus in the family Phoenicopteridae...

s (which may or may not be correct and altogether is not too unlikely) to form the supposed "proto-flamingo" family Scaniornithidae. However, the difference in age alone virtually rules out a close relationship between these two, and the early age of the Gallornis fossils makes it highly unlikely that this taxon
Taxon
|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...

 was allied to the flamingos. A more probable hypothesis, echoing the initial description of 1931, is that Gallornis was an early member of the Galloanserae, the clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...

 that eventually brought forth the Galliformes
Galliformes
Galliformes are an order of heavy-bodied ground-feeding domestic or game bird, containing turkey, grouse, chicken, New and Old World Quail, ptarmigan, partridge, pheasant, and the Cracidae. Common names are gamefowl or gamebirds, landfowl, gallinaceous birds or galliforms...

 (landfowl) and Anseriformes
Anseriformes
The order Anseriformes contains about 150 living species of birds in three extant families: the Anhimidae , Anseranatidae , and the Anatidae, which includes over 140 species of waterfowl, among them the ducks, geese, and swans.All species in the order are highly adapted for an aquatic existence at...

 (waterfowl) of our time. With the remains at hand, however, it cannot even be reliably determined whether Gallornis was a paleognath or a neognath, and it may actually be among the taxa closest to the LCA of all living birds from ostrich
Ostrich
The Ostrich is one or two species of large flightless birds native to Africa, the only living member of the genus Struthio. Some analyses indicate that the Somali Ostrich may be better considered a full species apart from the Common Ostrich, but most taxonomists consider it to be a...

es to sparrow
Sparrow
The sparrows are a family of small passerine birds, Passeridae. They are also known as true sparrows, or Old World sparrows, names also used for a genus of the family, Passer...

s. From all these considerations, it is obvious that more complete remains of this enigmatic taxon would be a find of invaluable significance for ornithology
Ornithology
Ornithology is a branch of zoology that concerns the study of birds. Several aspects of ornithology differ from related disciplines, due partly to the high visibility and the aesthetic appeal of birds...

.

Though the material is almost beyond recognition, a few features of the femur are still recognizable. In general shape it resembles the Neornithes. Notably, the lateral trochanter
Trochanter
In human anatomy, the trochanter is a part of the thigh bone. It can refer to:* Greater trochanter* Lesser trochanter* Third trochanter-See also:* Intertrochanteric crest* Intertrochanteric line...

ic crest is elevated over a large antitrochanteric facet, and somewhat recurved over it. The elevated lateral trochanteric crest is an autapomorphic feature of and plesiomorphic among Neornithes, as far as is known. It is widespread in the most ancient lineages of these, such as tinamou
Tinamou
The tinamous are a family comprising 47 species of birds found in Central and South America. One of the most ancient living groups of bird, they are related to the ratites. Generally ground dwelling, they are found in a range of habitats....

s, Galloanserae, shorebirds and seabird
Seabird
Seabirds are birds that have adapted to life within the marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same environmental problems and feeding niches have resulted in similar adaptations...

s, and changed fundamentally again especially in later landbird lineages.

The material of G. straeleni is highly unsuited for cladistic analysis. However, what uncertain results there are support the view that this is one of the most ancient birds in the modern sense known to date. Nonetheless, given that Gansus yumenensis, an ornithuran
Ornithurae
Ornithurae is the name of a natural group which includes all modern birds as well as their extinct relatives with plough-shaped pygostyles, a bone at the end of the tail which allows the tail feathers to fan and retract....

close to modern birds but probably not part of their lineage lived some dozen million years later, comparison of the Gallornis material with fossils of such more primitive birds seems warranted.
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