Odontognathae
Encyclopedia
Odontognathae is an extinct superorder of birds found widely in Kansas
. The superorder was originally proposed by Alexander Wetmore
, who attempted to link fossil birds with the presence of teeth, specifically of the orders Hesperornithiformes
and Ichthyornithiformes. As such they would be regarded as transitional fossil
s between the reptil
-like Archaeornithes
like Archaeopteryx and modern birds. They were described by Romer
as birds with essentially modern anatomy, but retaining teeth.
, the Odontognathae had short tails with a plowshare
-shaped pygostyle
and a well developed carina for flight muscle. The wings are generally without claws, though claws are found in some modern birds (the hoatzin
and in kiwi
s). They also shared the feature of intramandibular articulation, something that is actually absent in Archaeopteryx
, but found in many of its theropod relatives.
The brains of the Odontognathae appear to be somewhat simpler than those of modern birds and have retained some reptile
traits. Ornithologist Alan Feduccia
has used this, and the presence of the intramandibular articulation (a trait also found in mosasaur
s and living varanid lizards) as arguments that the Odontognathae and thus the birds as a whole have not evolved from theropod dinosaurs, but non-dinosaur Thecodont
s. This theory is contested by most paleontologists.
(the ancient birds). Today the name Neornithes is commonly used for the bird crown group
, the Odontognathae being united with them the group Ornithurae
.
Kansas
Kansas is a US state located in the Midwestern United States. It is named after the Kansas River which flows through it, which in turn was named after the Kansa Native American tribe, which inhabited the area. The tribe's name is often said to mean "people of the wind" or "people of the south...
. The superorder was originally proposed by Alexander Wetmore
Alexander Wetmore
Frank Alexander Wetmore was an American ornithologist and avian paleontologist.-Life:Wetmore studied at the University of Kansas...
, who attempted to link fossil birds with the presence of teeth, specifically of the orders Hesperornithiformes
Hesperornithiformes
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 Ichthyornithiformes. As such they would be regarded as transitional fossil
Transitional fossil
A transitional fossil is any fossilized remains of a lifeform that exhibits characteristics of two distinct taxonomic groups. A transitional fossil is the fossil of an organism near the branching point where major individual lineages diverge...
s between the reptil
Reptil
Reptil is a character from Marvel Comics. He is best known as a supporting member on The Super Hero Squad Show and a member of Avengers Academy in the comics.-Fictional character biography:...
-like Archaeornithes
Archaeornithes
The Archaeornithes, classically Archæornithes, is an extinct group of the first primitive, reptile-like like birds. It is an evolutionary grade of transitional fossils, the primitive birds halfway between dinosaur ancestors and the derived modern birds....
like Archaeopteryx and modern birds. They were described by Romer
Alfred Romer
Alfred Sherwood Romer was an American paleontologist and comparative anatomist and a specialist in vertebrate evolution.-Biography:...
as birds with essentially modern anatomy, but retaining teeth.
Traits
Unlike the dinosaur-like ArchaeornithesArchaeornithes
The Archaeornithes, classically Archæornithes, is an extinct group of the first primitive, reptile-like like birds. It is an evolutionary grade of transitional fossils, the primitive birds halfway between dinosaur ancestors and the derived modern birds....
, the Odontognathae had short tails with a plowshare
Plowshare
In agriculture, a plowshare is a component of a plow . It is the cutting or leading edge of a moldboard which closely follows the coulter when plowing....
-shaped pygostyle
Pygostyle
Pygostyle refers to a number of the final few caudal vertebrae fused into a single ossification, supporting the tail feathers and musculature. In modern birds, the rectrices attach to these....
and a well developed carina for flight muscle. The wings are generally without claws, though claws are found in some modern birds (the hoatzin
Hoatzin
The Hoatzin , also known as the Hoactzin, Stinkbird, or Canje Pheasant, is a species of tropical bird found in swamps, riverine forest and mangrove of the Amazon and the Orinoco delta in South America...
and in kiwi
Kiwi
Kiwi are flightless birds endemic to New Zealand, in the genus Apteryx and family Apterygidae.At around the size of a domestic chicken, kiwi are by far the smallest living ratites and lay the largest egg in relation to their body size of any species of bird in the world...
s). They also shared the feature of intramandibular articulation, something that is actually absent in Archaeopteryx
Archaeopteryx
Archaeopteryx , sometimes referred to by its German name Urvogel , is a genus of theropod dinosaur that is closely related to birds. The name derives from the Ancient Greek meaning "ancient", and , meaning "feather" or "wing"...
, but found in many of its theropod relatives.
The brains of the Odontognathae appear to be somewhat simpler than those of modern birds and have retained some reptile
Reptile
Reptiles are members of a class of air-breathing, ectothermic vertebrates which are characterized by laying shelled eggs , and having skin covered in scales and/or scutes. They are tetrapods, either having four limbs or being descended from four-limbed ancestors...
traits. Ornithologist Alan Feduccia
Alan Feduccia
Alan Feduccia is a paleornithologist, specializing in the origins and phylogeny of birds. He is now Professor Emeritus at the University of North Carolina. Feduccia's principal authored works include two books, The Age of Birds and The Origin and Evolution of Birds, and numerous papers in various...
has used this, and the presence of the intramandibular articulation (a trait also found in mosasaur
Mosasaur
Mosasaurs are large extinct marine lizards. The first fossil remains were discovered in a limestone quarry at Maastricht on the Meuse in 1764...
s and living varanid lizards) as arguments that the Odontognathae and thus the birds as a whole have not evolved from theropod dinosaurs, but non-dinosaur Thecodont
Thecodont
Thecodont , now considered an obsolete term, was formerly used to describe a diverse range of early archosaurs that first appeared in the Latest Permian and flourished until the end of the Triassic period...
s. This theory is contested by most paleontologists.
Classification
Classically, Odontognathiae was considered one of three superoders of Neornithes (modern birds) as opposed to ArchaeornithesArchaeornithes
The Archaeornithes, classically Archæornithes, is an extinct group of the first primitive, reptile-like like birds. It is an evolutionary grade of transitional fossils, the primitive birds halfway between dinosaur ancestors and the derived modern birds....
(the ancient birds). Today the name Neornithes is commonly used for the bird crown group
Crown group
A crown group is a group consisting of living representatives, their ancestors back to the most recent common ancestor of that group, and all of that ancestor's descendants. The name was given by Willi Hennig, the formulator of phylogenetic systematics, as a way of classifying living organisms...
, the Odontognathae being united with them the group Ornithurae
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....
.