Ornithopod

	Email		Print
	Bookmark		Link

Ornithopod

Ornithopods are a group of bird-hipped

Ornithischia

Ornithischia or Predentata is an extinct order of beaked, herbivore dinosaurs. The name ornithischia is derived from the Ancient Greek ornitheos meaning 'of a bird' and ischion meaning 'hip joint'....
dinosaur

Dinosaur

Dinosaurs were the dominant vertebrate animals of Landform ecosystems for over 160 million years, from the late Triassic Period until the end of the Cretaceous Period , when most of them became extinct in the Cretaceous?Tertiary extinction event....
s that started out as small, bipedal running

Cursorial

Cursorial is a biological term that describes an organism as being adapted specifically to running. It is typically used in conjunction with an animal's feeding habits or another important adaptation....
grazers, and grew in size and numbers until they became one of the most successful groups of herbivore

Herbivore

Herbivory is a form of predation in which an organism, known as an herbivore, heterotrophs principally autotrophs such as plants, algae and photosynthesizing bacteria....
s in the Cretaceous

Cretaceous

The Cretaceous , usually abbreviated K for its German translation Kreide, is a geologic period from circa to million years ago . In the geologic timescale, the Cretaceous follows on the Jurassic period and is followed by the Paleogene period....
world, and dominated the North America

North America

North America is the northern continent of the Americas, situated in the Earth's northern hemisphere and almost totally in the western hemisphere....
n landscape. Their major evolutionary advantage was the progressive development of a chewing apparatus that became the most sophisticated ever developed by a reptile

Reptile

Reptiles, or members of the class Reptilia, are air-breathing, cold-blooded vertebrates that have skin covered in scale as opposed to hair or feathers....
, rivaling that of modern mammal

Mammal

Mammals are a class of vertebrate animals whose name is derived from their distinctive feature, mammary glands, with which they feed their young....
s like the domestic cow.

Discussion

Ask a question about 'Ornithopod'

Start a new discussion about 'Ornithopod'

Answer questions from other users

Full Discussion Forum

Encyclopedia

Ornithopods are a group of bird-hipped

Ornithischia

Dinosaur

Cursorial

Herbivore

Herbivory is a form of predation in which an organism, known as an herbivore, heterotrophs principally autotrophs such as plants, algae and photosynthesizing bacteria....
s in the Cretaceous

Cretaceous

North America

Reptile

Reptiles, or members of the class Reptilia, are air-breathing, cold-blooded vertebrates that have skin covered in scale as opposed to hair or feathers....
, rivaling that of modern mammal

Mammal

Mammals are a class of vertebrate animals whose name is derived from their distinctive feature, mammary glands, with which they feed their young....
s like the domestic cow. They reached their apex in the duck-bills, before they were wiped out by the Cretaceous-Tertiary extinction event

Cretaceous-Tertiary extinction event

The Cretaceous?Tertiary extinction event, which occurred approximately , was a large-scale Extinction event of animal and plant species in a geologically short period of time....
along with all other non-avian dinosaur

Dinosaur

Continent

A continent is one of several large landmasses on Earth. They are generally identified by convention rather than any strict criteria, with seven regions commonly regarded as continents ? they are : Asia, Africa, North America, South America, Antarctica, Europe, and Australia ....
s, although the Antarctic remains are unnamed, and they are generally rare in the Southern Hemisphere

Southern Hemisphere

The Southern Hemisphere is the half of a planet that is south of the equator?the word sphere literally means 'half ball'. It is also that half of the celestial sphere south of the celestial equator....
.

Ornithopoda means "bird feet

Foot

The foot is an anatomical structure found in many animals. It is the terminal portion of a limb which bears weight and allows locomotion. In many animals with feet, the foot is a separate organ at the terminal part of the leg made up of one or more segments or bones, generally including claws or nails....
", from the Greek

Greek language

Greek is an Indo-European languages native to the southern Balkan peninsula, the language of the Greek people. It forms an independent branch within Indo-European....
ornis ("bird") and pous ("feet"); this refers to their characteristic three-toe

Toe

Toes are the Digit s of the foot of an animal. Many animal species such as cats walk on their toes, and are described as being digitigrade....
d feet, although many early forms retained four toes. They were also characterized by having no armor, the development of a horny beak

Beak

The beak, bill or rostrum is an external anatomical structure of birds which, in addition to eating, is used for Personal grooming#In animals, manipulating objects, killing prey, probing for food, Courtship#Courtship in the animal kingdom and feeding their young....
, an elongated pubis

Pubis (bone)

The android pubic bone is the ventral and anterior of the three principal bones composing either half of the pelvis.It is covered by a layer of fat, which is covered by the mons pubis....
that eventually extended past the ilium

Ilium (bone)

The ilium is the uppermost and largest bone of the pelvis, and appears in most vertebrates including mammals and birds, but not bony fish. All reptiles have an ilium except snakes, although some snake species have a tiny bone which is considered to be an ilium....
, and a missing hole in the lower jaw

Jaw

The jaw is either of the two opposable structures forming, or near the entrance to the mouth.The term jaws is also broadly applied to the whole of the structures constituting the vault of the mouth and serving to open and close it and is part of the body plan of most animals....
. A variety of ornithopods and related cerapods

Cerapoda

Cerapoda is a clade or suborder of the order Ornithischia. They are the sister group of the Thyreophora within the clade Genasauria. They are divided either into two or three groups....
had thin cartilaginous

Cartilage

Cartilage is a type of dense connective tissue. It is composed of specialized cells called chondrocyte that produce a large amount of extracellular matrix composed of collagen fibers, abundant ground substance rich in proteoglycan, and elastin fibers....
plates along the outside of the ribs; in some cases, these plates mineralized and were fossilized. The function of these intercostal plates is unknown. They have been found with Hypsilophodon
Hypsilophodon

Hypsilophodon is an ornithopod dinosaur genus from the Early Cretaceous Period of Europe. It was a small bipedal animal with an herbivore or possibly omnivore diet....
, Othnielosaurus
Othnielosaurus

Othnielosaurus is a genus of ornithischian dinosaur that lived about 155 to 148 million years ago, during the Late Jurassic-age Morrison Formation of the western United States....
, Parksosaurus
Parksosaurus

Parksosaurus was a genus of hypsilophodont ornithopod dinosaur from the Maastrichtian-age Upper Cretaceous Horseshoe Canyon Formation of Alberta, Canada....
, Talenkauen
Talenkauen

Talenkauen is a genus of Basal iguanodont dinosaur from the Maastrichtian-age Upper Cretaceous Pari Aike Formation of Lake Viedma, Santa Cruz Province , Argentina....
, Thescelosaurus
Thescelosaurus

Thescelosaurus was a genus of small ornithopod dinosaur that appeared at the very end of the Late Cretaceous period in North America. It was a member of the last dinosaurian fauna before the Cretaceous-Tertiary extinction event around 65.5 million years ago....
, and Macrogryphosaurus
Macrogryphosaurus

Macrogryphosaurus is a genus of Basal iguanodont dinosaur from the Turonian-early Coniacian age Upper Cretaceous Portezuelo Formation of Patagonia, Argentina....
to date.

The early ornithopods were only about 1 meter (3 feet) long, but probably very fast. They had a stiff tail, like the theropods

Theropoda

Theropods are a group of bipedal saurischian dinosaurs. Although they were primarily carnivorous, a number of theropod families evolved herbivore during the Cretaceous Period ....
, to help them balance as they ran on their hind legs. Later ornithopods became more adapted to grazing on all fours; their spine

Vertebral column

In human anatomy, the vertebral column is a column of 24 vertebrae, the sacrum, intervertebral discs, and the coccyx situated in the dorsum aspect of the torso, separated by spinal discs....
s curved, and came to resemble the spines of modern ground-feeders like the bison

Bison

Bison is a taxonomic group containing six species of large even-toed ungulates within the subfamily Bovinae. Only two of these species still exist: the American bison and the European bison, or wisent , each with two subspecies....
. As they became more adapted to eating while bent over, they became semi-quadruped

Quadruped

Quadrupedalism is a form of Terrestrial locomotion in animals using four limbs or leg . An animal or machine that usually moves in a quadrupedal manner is known as a quadruped, meaning "four feet" ....
al; still running on two legs, and comfortable reaching up into trees; but spending most of their time walking or grazing while on all fours. The taxonomy of dinosaurs previously ascribed to the hypsilophodontidae is problematic. The group previously consisted of all non-Iguanodontid bipedal ornithischians, but a phylogenetic reappraisal has shown such species to be paraphyletic. As such, the hypsolophodont family is represented only by Hypsilophodon
Hypsilophodon

Hypsilophodon is an ornithopod dinosaur genus from the Early Cretaceous Period of Europe. It was a small bipedal animal with an herbivore or possibly omnivore diet....
.

Later ornithopods became larger, but never rivaled the incredible size of the long-necked, long-tailed sauropods that they partially supplanted; the largest, like the Edmontosaurus
Edmontosaurus

Edmontosaurus is a genus of hadrosaurid dinosaur. Its fossils have been found in rocks of western North America that date to the late Campanian and Maastrichtian Stage of the Cretaceous Geologic time scale#Terminology, between 73 and 65.5 million years ago....
and Shantungosaurus
Shantungosaurus

Shantungosaurus, meaning "Shandong Lizard", is a genus of flat headed hadrosaurid dinosaurs found in the Late Cretaceous Wangshi Formation of the Shandong Peninsula in China....
, never grew far beyond 15 meters (50 feet).

Historically, most indeterminate ornithischian biped

Biped

Bipedalism is a form of terrestrial locomotion where an organism Motion by means of its two rear limbs, or legs. An animal or machine that usually moves in a bipedal manner is known as a biped , meaning "two feet" ....
s were lumped in as ornithopods. Most have since been reclassified as basal

Basal (phylogenetics)

In phylogenetics, a basal clade is the earliest clade to branch in a larger clade; it appears at the base of a cladogram.A basal group form an outgroup to the rest of the clade, such as in the following example:...
members of quadrupedal taxa like Marginocephalia

Marginocephalia

Marginocephalia is a clade of ornithischian dinosaurs that includes the thick-skulled pachycephalosauria, and horned ceratopsians. They were all herbivores, walking on two or four legs, and are characterized by a bony ridge or frill the back of the skull....
; and some, like the "bone-headed" pachycephalosaurids, have been given their own taxa.

Classification

Taxonomy

Infraorder Ornithopoda

Anabisetia
Anabisetia

Anabisetia is a genus of ornithopod dinosaur from the Late Cretaceous Period of Patagonia, South America. It was a small bipedal herbivore, almost seven feet long....
Bihariosaurus
Bihariosaurus

Bihariosaurus was a genus of camptosaurid dinosaur from Late Cretaceous Romania. The type species, Bihariosaurus bauxiticus, was described by Marinescu in 1989....
Changchunsaurus
Changchunsaurus

Changchunsaurus was a genus of small herbivorous ornithopod dinosaur from the Early Cretaceous Quantou Formation of Gongzhuling, Jilin, People's Republic of China....
Fukuisaurus
Fukuisaurus

Fukuisaurus is a genus of herbivory dinosaur from the Early Cretaceous. It was an ornithopod which lived in what is now Japan. Remains of Fukuisaurus were discovered in 1990, in Katsuyama, Fukui Prefecture, in rocks from the Kitadani Formation....
Jeholosaurus
Jeholosaurus

Jeholosaurus is the name given to a genus of dinosaur from the Early Cretaceous Period . It lived in what is now China and its fossils have been found in the Yixian Formation....
Lurdusaurus
Lurdusaurus

Lurdusaurus is a genus of large ornithopod dinosaur which lived in the Aptian faunal stage of the Early Cretaceous, about 121 to 112 million years ago....
Muttaburrasaurus
Muttaburrasaurus

Muttaburrasaurus is a genus of herbivorous ornithopod dinosaur related to Camptosaurus and Iguanodon, from what is now northeastern Australia between 100 and 98 million years ago during the early Cretaceous Period ....
Siluosaurus
Siluosaurus

Siluosaurus is a genus of ornithopod dinosaur from the Barremian-Albian-age Lower Cretaceous Xinminbao Group of Gansu, People's Republic of China....
Talenkauen
Talenkauen

Talenkauen is a genus of Basal iguanodont dinosaur from the Maastrichtian-age Upper Cretaceous Pari Aike Formation of Lake Viedma, Santa Cruz Province , Argentina....
Tenontosaurus
Tenontosaurus

Tenontosaurus is a genus of medium- to large-sized ornithopod dinosaur. It was formerly thought to be a 'hypsilophodont', but since Hypsilophodontia is no longer considered a clade, it is now considered to be a very primitive iguanodont....
Family Camptosauridae
Family Dryosauridae
Family Hypsilophodont
Hypsilophodont

Hypsilophodonts were small ornithopod dinosaurs, regarded as fast, herbivorous bipeds on the order of 1-2 meters long . They are known from Asia, Australia, Europe, North America, and South America, from rock formation of Middle Jurassic to late Cretaceous age....
idae*
Paraphyly

In phylogenetics, a group of organisms is said to be paraphyletic if the group contains its most recent common ancestor Common descent but does not contain all the descendants of that ancestor....
Family Iguanodon
Iguanodon

Iguanodon is a genus of ornithopod dinosaur that lived roughly halfway between the first of the swift bipedalism hypsilophodontids and the ornithopods' culmination in the hadrosaurid dinosaurs....
tidae
Family Rhabdodontidae
Rhabdodontidae

Rhabdodontids were herbivorous ornithopod dinosaurs from the Late Cretaceous Period. Rhabdodontids were similar to large, robust hypsilophodonts, with deep skulls and jaws....
Superfamily Hadrosauroidea
Hadrosauroidea

Hadrosauroidea is a clade or superfamily of ornithischian dinosaurs that includes the "duck-billed" dinosaurs, or hadrosaurids, and their close relatives....

Phylogeny

Cladogram after Sues & Norman (1990) and Weishampel & Heinrich (1992).

Ornithopoda |-?Siluosaurus
Siluosaurus

Siluosaurus is a genus of ornithopod dinosaur from the Barremian-Albian-age Lower Cretaceous Xinminbao Group of Gansu, People's Republic of China....
|-?Changchunsaurus
Changchunsaurus

Changchunsaurus was a genus of small herbivorous ornithopod dinosaur from the Early Cretaceous Quantou Formation of Gongzhuling, Jilin, People's Republic of China....
`--Euornithopoda |--Hypsilophodont

Hypsilophodont

Hypsilophodonts were small ornithopod dinosaurs, regarded as fast, herbivorous bipeds on the order of 1-2 meters long . They are known from Asia, Australia, Europe, North America, and South America, from rock formation of Middle Jurassic to late Cretaceous age....
ia `--Iguanodontia |--Tenontosaurus
Tenontosaurus

Tenontosaurus is a genus of medium- to large-sized ornithopod dinosaur. It was formerly thought to be a 'hypsilophodont', but since Hypsilophodontia is no longer considered a clade, it is now considered to be a very primitive iguanodont....
`--+--Rhabdodontidae

Rhabdodontidae

Rhabdodontids were herbivorous ornithopod dinosaurs from the Late Cretaceous Period. Rhabdodontids were similar to large, robust hypsilophodonts, with deep skulls and jaws....
|-?Muttaburrasaurus
Muttaburrasaurus

Muttaburrasaurus is a genus of herbivorous ornithopod dinosaur related to Camptosaurus and Iguanodon, from what is now northeastern Australia between 100 and 98 million years ago during the early Cretaceous Period ....
`--Euiguanodontia |--Anabisetia
Anabisetia

Anabisetia is a genus of ornithopod dinosaur from the Late Cretaceous Period of Patagonia, South America. It was a small bipedal herbivore, almost seven feet long....
|--Gasparinisaura
Gasparinisaura

Gasparinisaura is the name of a genus of dinosaur from the Late Cretaceous. Its fossils were found in Argentina. The type species, Gasparinisaura cincosaltensis, was described in 1996 by Coria and Salgado....
`--Dryomorpha |--Dryosauridae `--Ankylopollexia |-?Bihariosaurus
Bihariosaurus

Bihariosaurus was a genus of camptosaurid dinosaur from Late Cretaceous Romania. The type species, Bihariosaurus bauxiticus, was described by Marinescu in 1989....
|-?Talenkauen
Talenkauen

Talenkauen is a genus of Basal iguanodont dinosaur from the Maastrichtian-age Upper Cretaceous Pari Aike Formation of Lake Viedma, Santa Cruz Province , Argentina....
|--Camptosauridae `--Iguanodontoidea |--Lurdusaurus
Lurdusaurus

Lurdusaurus is a genus of large ornithopod dinosaur which lived in the Aptian faunal stage of the Early Cretaceous, about 121 to 112 million years ago....
|--Lanzhousaurus
Lanzhousaurus

Lanzhousaurus is the name given to a genus of dinosaur discovered in 2005. Lanzhousaurus lived in the Gansu region of what is now China during the Early Cretaceous....
`--Hadrosauriformes |--Iguanodon
Iguanodon

Iguanodon is a genus of ornithopod dinosaur that lived roughly halfway between the first of the swift bipedalism hypsilophodontids and the ornithopods' culmination in the hadrosaurid dinosaurs....
`--+--Ouranosaurus
Ouranosaurus

Ouranosaurus was an unusual iguanodont that lived during the early Cretaceous about 110 mya in what is now Africa. Ouranosaurus measured about 7 metre long and weighed about 4 tons....
`--+--Fukuisaurus
Fukuisaurus

Fukuisaurus is a genus of herbivory dinosaur from the Early Cretaceous. It was an ornithopod which lived in what is now Japan. Remains of Fukuisaurus were discovered in 1990, in Katsuyama, Fukui Prefecture, in rocks from the Kitadani Formation....
`--Hadrosauroidea

Hadrosauroidea

Hadrosauroidea is a clade or superfamily of ornithischian dinosaurs that includes the "duck-billed" dinosaurs, or hadrosaurids, and their close relatives....

External links

, by Justin Tweet, from Thescelosaurus!
, by Thomas R. Holtz, Jr.