Theropoda
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Durova
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{{Taxobox
| name = Theropods
| fossil_range = [[Late Triassic]] - [[Late Cretaceous]] <br/><small>(excluding birds)</small>
| image = TrexFoot.jpg
| image_width = 200px
| image_caption = ''[[Tyrannosaurus]]'' foot
| regnum = [[Animal]]ia
| phylum = [[Chordate|Chordata]]
| classis = [[Reptile|Sauropsida]]
| superordo = [[Dinosaur]]ia
| ordo = [[Saurischia]]
| subordo = '''Theropoda'''
| subordo_authority = [[Othniel Charles Marsh|Marsh]], 1881
| subdivision_ranks = [[Infraorder]]s
| subdivision =
* †[[Carnosauria]]
* †[[Ceratosauria]]
* †[[Deinonychosauria]]
* †[[Ornithomimosauria]]
* †[[Oviraptorosauria]]
* (unranked) [[Avialae]]
}}
'''Theropods''' ({{pronEng|ˈθɪərəpɒd}}, ''theropoda'' {{IPA|/θiːˈrɒpədə/}} 'beast feet') are a group of [[bipedal]] [[saurischian]] [[dinosaur]]s. Although they were primarily carnivorous, a number of theropod families evolved [[herbivore|herbivory]] during the [[Cretaceous]] [[Period (geology)|Period]]. Theropods first appear during the [[Carnian]] age of the Late [[Triassic]] about 220 million years ago ([[mya (unit)|MYA]]) and were the sole large terrestrial carnivores from the [[Early Jurassic]] until the close of the [[Cretaceous]], about 65 MYA. Today, they are represented by the 9,300 living species of [[bird]]s, which evolved in the [[Late Jurassic]] from small specialized [[coelurosaur]]ian dinosaurs.
Among the features linking theropods to birds are the three-toed foot, a [[furcula]] (wishbone), air-filled bones and (in some cases) feathers and [[brooding]] of the [[Egg (biology)|egg]]s.
==Evolutionary history==
During the late [[Triassic]], a number of primitive proto-theropod and theropod dinosaurs existed and evolved alongside each other.
The earliest and most primitive of the carnivorous dinosaurs were ''[[Eoraptor]]'' of [[Argentina]] and the [[Herrerasauria|herrerasaurs]]. The herrerasaurs existed from the early late Triassic (Late [[Carnian]] to Early [[Norian]]). They were found in [[North America]] and [[South America]] and possibly also [[India]] and Southern [[Africa]]. The herrerasaurs were characterised by a [[mosaic evolution|mosaic]] of primitive and advanced features. Some paleontologists have in the past considered the herrerasaurians to be members of Theropoda, though they are now thought to be [[Basal (phylogenetics)|basal]] saurischians, and may even have evolved prior to the saurischian-ornithischian split.
[[Image:Dinosaur_track.jpg|left|thumb|Theropod footprint.]]
The earliest and most primitive unambiguous theropods (or alternatively, [[Eutheropoda]] - 'True Theropods') are the [[Coelophysidae]]. The [[Coelophysidae]] (''[[Coelophysis]]'', ''[[Megapnosaurus]]'') were a group of widely distributed, lightly built and apparently gregarious animals. They included small hunters like ''Coelophysis'' and larger (6 meters) predators like ''[[Dilophosaurus]]''. These successful animals continued from the Late Carnian (early Late Triassic) through to the [[Toarcian]] (late [[Early Jurassic]]). Although in the early [[cladism|cladistic]] classifications they were included under the [[Ceratosauria]] and considered a side-branch of more advanced theropods,<ref name="rowe&gauthier1990">Rowe, T., and Gauthier, J., (1990). "Ceratosauria." Pp. 151-168 in Weishampel, D. B., Dodson, P., and Osmólska, H. (eds.), ''The Dinosauria'', University of California Press, Berkley, Los Angeles, Oxford.</ref> they may have been ancestral to all other theropods (which would make them a [[paraphyletic]] group.<ref name="mortimerdml2001">Mortimer, M. (2001). "[http://dml.cmnh.org/2001Jul/msg00110.html Rauhut's Thesis]", Dinosaur Mailing List Archives, 4 Jul 2001.</ref><ref name="carranoetal2002">Carrano, M. T., Sampson, S. D. and Forster, C. A., (2002). "The osteology of ''Masiakasaurus knopfleri'', a small abelisauroid (Dinosauria: Theropoda) from the Late Cretaceous of Madagascar." ''Journal of Vertebrate Paleontology'', '''22'''(3): 510-534.</ref>
The somewhat more advanced true [[Ceratosauria]] (including ''[[Ceratosaurus]]'' and ''[[Carnotaurus]]'') appeared during the Early Jurassic and continued through to the Late Jurassic in [[Laurasia]]. They competed quite well alongside their more advanced tetanuran relatives and - in the form of the [[abelisaur]] lineage - lasted to the end of the Cretaceous in [[Gondwana]].
[[Image:Tetanurae skelgon.JPG|thumb|right|Skeletal reconstructions of several theropod dinosaurs.]]
The [[Tetanurae]] are more specialised again than the Ceratosaurs. They are subdivided into [[Megalosauroidea]] (alternately [[Spinosauroidea]] or [[Torvosauroidea]]) and the [[Avetheropoda]]. They were most common during the Middle Jurassic but continued to the Middle Cretaceous. The latter [[clade]] - as their name indicates - were more closely related to birds and are again divided into the [[Carnosauria]] (including ''[[Allosaurus]]'') and the [[Coelurosauria]], a very large and diverse dinosaur group that was especially common during the Cretaceous.
Thus, during the late Jurassic, there were no fewer than four distinct lineages of theropods - ceratosaurs, megalosaurs, carnosaurs, and coelurosaurs - preying on the abundance of small and large herbivorous dinosaurs. All four groups survived into the Cretaceous, although only two - the abelisaurs and the coelurosaurs - seem to have made it to end of the period, where they were geographically separate, the abelisaurs in Gondwana, and the coelurosaurs in [[Asiamerica]].
Of all the theropod groups, the coelurosaurs were by far the most diverse. Some coelurosaur clades that flourished during the Cretaceous were the [[Tyrannosauridae|tyrannosaurids]] (including ''[[Tyrannosaurus]]'') the [[Dromaeosauridae|dromaeosaurids]] (including ''[[Velociraptor]]'' and ''[[Deinonychus]]'', which are remarkably similar in form to the oldest known bird, ''[[Archaeopteryx]]''<ref name="ostrom1969">Ostrom, J.H. (1969). "Osteology of ''Deinonychus antirrhopus'', an unusual theropod from the Lower Cretaceous of Montana." ''Peabody Museum Natural History Bulletin'', '''30''': 1-165.</ref><ref name="paul1988">Paul, G.S. (1988). ''Predatory Dinosaurs of the World''. New York: Simon and Schuster Co. (ISBN 0-671-61946-2)</ref>), the bird-like [[Troodontidae|troodontids]] and [[Oviraptorosauria|oviraptorosaurs]], the [[Ornithomimosauria|ornithomimosaurs]] (or "ostrich dinosaurs"), the strange giant-clawed herbivorous [[Therizinosauridae]], and the [[bird]]s, which are the only dinosaur lineage to survive the end Cretaceous mass-extinction.<ref name="dingus&rowe1998">Dingus, L. and Rowe, T. (1998). ''The Mistaken Extinction: Dinosaur Evolution and the Origin of Birds''. Freeman.</ref> While the roots of these various groups must have been in the Late or possibly even the Middle Jurassic, they only became abundant during the Early Cretaceous. A few paleontologists, such as [[Gregory S. Paul]], have suggested that some or all of these advanced theropods were actually descended from flying dinosaurs or proto-birds like ''Archaeopteryx'' that lost the ability to fly and returned to a terrestrial habitat.<ref name=paul2002>Paul, G.S. (2002). ''Dinosaurs of the Air: The Evolution and Loss of Flight in Dinosaurs and Birds.'' Baltimore: Johns Hopkins University Press. 472 pp. (ISBN 0-8018-6763-0)</ref>
==Classification==
===History of classification===
The name Theropoda (meaning "beast feet") was first coined by [[Othniel Charles Marsh|O.C. Marsh]] in 1881. Marsh initially named Theropoda as a [[Order (biology)|suborder]] to include the [[Family (biology)|family]] [[Allosauridae]], but later expanded its scope, re-ranking it as an [[Order (biology)|order]] to include a wide array of "carnivorous" dinosaur families, including [[Megalosauridae]], [[Compsognathidae]], [[Ornithomimidae]], [[Plateosauridae]] and [[Anchisauridae]] (now known to be herbivorous [[Prosauropoda|prosauropods]]) and [[Hallopodidae]] (now known to be relatives of crocodilians). Due to the scope of Marsh's Order Theropoda, it came to replace a previous taxonomic group that Marsh's rival [[Edward Drinker Cope|E.D. Cope]] had created in 1866 for the carnivorous dinosaurs, '''Goniopoda''' ("angled feet").<ref name="rauhut2003">Rauhut, O.W. (2003). ''The Interrelationships and Evolution of Basal Theropod Dinosaurs''. Blackwell Publishing, 213 pp. ISBN:090170279X</ref>
By the early 20th Century, some paleontologists, such as [[Friedrich von Huene]], no longer considered carnivorous dinosaurs to have formed a natural group. Huene abandoned the name Theropoda, instead using [[Harry Seeley]]'s Order [[Saurischia]], which Huene divided into the suborders [[Coelurosauria]] and [[Pachypodosauria]]. Huene placed most of the small theropod groups into Coelurosauria, and the large theropods and prosauropods into Pachypodosauria, which he considered ancestral to the [[Sauropoda]] (prosauropods were still thought of as carnivorous at this time, owing to the incorrect association of [[Rauisuchia|rauisuchian]] skulls and teeth with prosauropod bodies, in animals such as ''[[Teratosaurus]]'').<ref name="rauhut2003"/> In W.D. Matthew and [[Barnum Brown]]'s 1922 description of the first known [[Dromaeosauridae|dromaeosaurid]] (''[[Dromaeosaurus|Dromaeosaurus albertensis]]''<ref name="matthew&brown1922">Matthew, W. D., and Brown, B. (1922) "The family Deinodontidae, with notice of a new genus from the Cretaceous of Alberta." ''Bulletin of the American Museum of Natural History'', '''46''': 367-385.</ref>), they became the first paleontologists to exclude prosauropods from the carnivorous dinosaurs, and attempted to revive the name Goniopoda for that group, though neither of these suggestions were accepted by other scientists.<ref name="rauhut2003"/>
It was not until 1956 that Theropoda came back into use as a [[taxon]] containing the carnivorous dinosaurs and their descendants, when [[Alfred Romer]] re-classified the Order Saurischia into two suborders, Theropoda and [[Sauropoda]]. This basic division has survived into modern paleontology, with the exception of, again, the Prosauropoda, which Romer included as an [[Order (biology)|infraorder]] of theropods. Romer also maintained a division between Coelurosauria and [[Carnosauria]] (which he also ranked as infraorders). This dichotomy was upset by the discovery of ''[[Deinonychus]]'' and ''[[Deinocheirus]]'' in 1969, neither of which could be classified easily as "carnosaurs" or "coelurosaurs." In light of these and other discoveries, by the late 1970s [[Rinchen Barsbold]] created a new series of theropod infraorders: Coelurosauria, [[Deinonychosauria]], [[Oviraptorosauria]], Carnosauria, [[Ornithomimosauria]], and [[Deinocheirosauria]].<ref name="rauhut2003"/>
With the advent of [[cladistics]] and [[phylogenetic nomenclature]] in the 1980s, and their development in the 1990s and 2000s, a clearer picture of theropod relationships began to emerge. Several major theropod groups were named by [[Jacques Gauthier]] in 1986, including the [[clade]] [[Tetanurae]] for one branch of a basic theropod split with another group, the [[Ceratosauria]]. As more information about the link between dinosaurs and [[bird]]s came to light, the more bird-like theropods were grouped in the clade [[Maniraptora]] (also named by Gauthier in 1986). These new developments also came with a recognition among most scientists that birds arose directly from maniraptoran theropods and, with the abandonment of ranks in cladistic classification, the re-evaluation of birds as a subset of theropod dinosaurs that happened to have survived the Mesozoic extinctions into the present.<ref name="rauhut2003"/>
===Taxonomy===
* '''Suborder Theropoda'''
** ''[[Agnosphitys]]''
** ''[[Chindesaurus]]''
** ''[[Guaibasaurus]]''
** '''Infraorder [[Ceratosauria]]'''
*** Family [[Ceratosauridae]]
*** Superfamily [[Abelisauroidea]]
*** Superfamily [[Coelophysoidea]]
** '''Clade [[Tetanurae]]'''
*** Superfamily [[Spinosauroidea]]
*** '''Infraorder [[Carnosauria]]'''
**** Superfamily [[Allosauroidea]]
*** '''Clade [[Coelurosauria]]'''
**** Family [[Coeluridae]]
**** Family [[Compsognathidae]]
**** Superfamily [[Tyrannosauroidea]]
**** '''Infraorder [[Ornithomimosauria]]'''
**** '''Clade [[Maniraptora]]'''
***** Family [[Scansoriopterygidae]]
***** '''Superfamily [[Therizinosaur]]oidea
***** '''Infraorder '''[[Deinonychosauria]]'''
****** Family [[Dromaeosauridae]]
****** Family [[Troodontidae]]
***** '''Infraorder [[Oviraptorosauria]]'''
===Phylogeny===
The following [[cladogram]] is adapted from Weishampel ''et al.'', 2004.<ref name="weishampel2004">Weishampel, D.B., Dodson, P., and Osmólska, H. (eds.) (2004). ''The Dinosauria'', Second Edition. Berkeley: University of California Press, 861 pp.</ref>
{{clade| style=font-size:100%;line-height:80%
|label1='''Theropoda'''
|1={{clade
|label1=<font color=white>unnamed</font>
|1={{clade
|label1=[[Ceratosauria]]
|1={{clade
|1=?[[Coelophysoidea]]
|label2=[[Neoceratosauria]]
|2={{clade
|1=[[Ceratosauridae]]
|2=[[Abelisauroidea]]
}}
}}
|label2=[[Tetanurae]]
|2={{clade
|1=[[Spinosauroidea]]
|label2=[[Avetheropoda]]
|2={{clade
|label1=[[Carnosauria]]
|1={{clade
|1=''[[Monolophosaurus]]''
|2=[[Allosauroidea]]
}}
|label2=[[Coelurosauria]]
|2={{clade
|1=[[Compsognathidae]]
|label2=[[Tyrannoraptora]]
|2={{clade
|1=[[Tyrannosauroidea]]
|label2=[[Maniraptoriformes]]
|2={{clade
|1=[[Ornithomimosauria]]
|label2=[[Maniraptora]]
|2={{clade
|1=[[Oviraptorosauria]] (incl. [[Therizinosauroidea]])
|label2=[[Paraves]]
|2={{clade
|label1=<font color=white>unnamed</font>
|1={{clade
|label1=[[Eumaniraptora]]
|1={{clade
|1=[[Deinonychosauria]]
|2=[[Avialae]]
}}
}}
}}
}}
}}
}}
}}
}}
}}
}}
}}
}}
==Size==
[[Image:Largesttheropods.svg|thumb|right|300px|Size comparison of selected giant theropod dinosaurs.]]
''[[Tyrannosaurus]]'' was the largest and most popular theropod known to the general public for many decades. Since its discovery, however, a number of other giant carnivorous dinosaurs have been described, including ''[[Spinosaurus]]'', ''[[Carcharodontosaurus]]'', ''[[Giganotosaurus]]'', ''[[Tyrannotitan]]'' and ''[[Mapusaurus]]''.The original ''Spinosaurus'' specimens (as well as newer fossils described in 2006) support the idea that ''Spinosaurus'' is larger than ''Tyrannosaurus'', showing that ''Spinosaurus'' was possibly 6 meters longer and at least 1 metric ton heavier than ''Tyrannosaurus''. There is still no clear scientific explanation for exactly why these animals grew so much larger than the predators that came before and after them. Parallel to this, the smallest known theropod is the [[bee hummingbird]].
==References==
{{reflist}}
{{commonscat|Theropoda}}
[[Category:Theropods| ]]
{{portalpar|Dinosaurs}}
[[ca:Teròpode]]
[[cs:Theropoda]]
[[de:Theropoda]]
[[es:Theropoda]]
[[eo:Teropodoj]]
[[fa:جانورپایان]]
[[fr:Theropoda]]
[[ko:수각류]]
[[it:Theropoda]]
[[he:תרופודה]]
[[lt:Plėšrieji dinozaurai]]
[[hu:Theropoda]]
[[nl:Theropoda]]
[[ja:獣脚類]]
[[pl:Teropody]]
[[pt:Theropoda]]
[[ro:Theropod]]
[[ru:Тероподы]]
[[simple:Theropoda]]
[[sk:Theropoda]]
[[fi:Teropodit]]
[[sv:Theropoder]]
[[uk:Тероподи]]
[[vo:Theropoda]]
[[zh:獸腳亞目]]