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| + | [[File:JW_Concavenator.png|thumb|274px]]'''''Concavenator''''' is a [[genus]] of [[theropod]] [[dinosaur]] that lived approximately 130 million years ago during the early [[Cretaceous]] period ([[Barremian]] stage). The [[type species]] is ''C. corcovatus''; ''Concavenator corcovatus'' means "hump backed hunter from [[Cuenca (province)|Cuenca]]".<ref name="refname1" group=""/> The fossil was discovered in the [[Las Hoyas]] fossil site of [[Spain]] by [[Paleonthologist|paleontologists]] José Luis Sanz, Francisco Ortega and Fernando Escaso from the [[Universidad Autónoma de Madrid|Autonomous University of Madrid]]<ref name="refname3" group=""/> and the [[Universidad Nacional de Educación a Distancia|National University of Distance Learning]].<ref name="refname1" group=""/> |
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| − | ==Intro== |
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| − | Concavenator is a recently discovered theropod that lived 130 million years ago in what is now Spain. It was one of the top predators in its ecosystem, and was certainly pretty weird looking. Above its waist was a fin-like hump. This hump could have been more slender like the sail of such dinosaurs as [[Baryonyx]], and [[Spinosaurus]]. In this case, it would have been used for display, or to regulate body temperature. One of the scientists involved in its discovery, Fransico Ortega, says it is "most plausible" that the hump was more fleshy, and stored fat, like a modern day Zebu, or camel. Another interesting feature is the presence of "quills" that may be ancestors of the modern feather on Concavenator's arms. Last, but not least, impressions of this dinosaur's skin were found, and this skin was composed of alligator-like scales. This not only helps in accurately visualizing Concavenator, but may help us find out more about what dinosaurs in general looked like. |
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| − | ==Fact File== |
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| − | Length: 6 metres[[File:Concavenator.jpg|thumb|348px]] |
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| + | ==Description== |
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| − | Height: 2.5 metres |
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| + | [[Image:Concavenator corcovatus.jpg|thumb|left|Fernando Escaso, Francisco Ortega, and José Luis Sanz working on ''Concavenator'']] |
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| + | [[File:Concavenator SIZE.png|thumb|left|150px|Size compared to a human.]] |
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| + | ''Concavenator'' was a medium-sized (roughly 6 meters (20 feet) long) primitive [[Carcharodontosauridae|carcharodontosaurian]] dinosaur possessing several unique features. Two extremely tall vertebrae in front of the hips formed a tall but narrow and pointed crest (possibly supporting a hump) on the dinosaur's back.<ref name=description/> The function of such crests is currently unknown. Paleontologist Roger Benson from [[Cambridge University]] speculated that one possibility is that "it is analogous to head-crests used in visual displays", but the Spanish scientists who discovered it noted it could also be a thermal regulator.<ref name="refname1" group=""/> |
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| + | Additionally, the forelimb (ulna) of ''Concavenator'' preserved evidence of what may be [[quill knob]]s or [[Homology (biology)|homologous]] structures, an anatomical feature so far known only in animals with large, quilled [[feather]]s on the forelimb.<ref name=description>{{cite journal | last1 = Ortega | first1 = F. | last2 = Escaso | first2 = F. | last3 = Sanz | first3 = J.L. | year = 2010 | title = A bizarre, humped Carcharodontosauria (Theropoda) from the Lower Cretaceous of Spain | url = http://pagina.jccm.es/museociencias/Ortega_etal_2010_Tero_Concavenator_Ki_Cuenca_esp_nature09181.pdf | format = PDF | journal = Nature | volume = 467 | issue = 7312| pages = 203–206 | doi = 10.1038/nature09181 | pmid = 20829793 }}</ref> |
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| − | Weight: 1 tonne |
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| + | ==Feathers and scales== |
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| − | Diet: [[Carnivore|Carnivorous ]] |
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| + | [[File:Concavenator in a pond.jpg|left|thumb|Restoration showing hypothetical integument]] |
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| − | ==Prey== |
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| + | ''Concavenator'' had structures resembling quill knobs on its forearm, a feature known only in birds and other feathered theropods, such as ''[[Velociraptor]]''. Quill knobs are created by ligaments which attach to the feather follicle, and since scales do not form from follicles, the authors ruled out the possibility that they could indicate the presence of long display scales on the arm. Instead, the knobs probably anchored simple, hollow, quill-like structures. Such structures are known both in [[Coelurosauria|coelurosaurs]] such as ''[[Dilong (dinosaur) | Dilong]]'' and in some [[Ornithischia|ornithischians]] like ''[[Tianyulong]]'' and ''[[Psittacosaurus]]''. If the ornithischian quills are homologous with bird feathers, their presence in an [[allosauroid]] like ''Concavenator'' would be expected.<ref name=description/> However, if ornithischian quills are not related to feathers, the presence of these structures in ''Concavenator'' would show that feathers had begun to appear in earlier, more primitive forms than coelurosaurs. Feathers or related structures would then likely be present in the first members of the clade [[Neotetanurae]], which lived in the [[Middle Jurassic]]. No impressions of any kind of integument were found near the arm, although extensive scale impressions were preserved on other portions of the body, including broad, rectangular scales on the underside of the tail, bird-like scutes on the feet, and plantar pads on the undersides of the feet.<ref name=description/> |
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| − | Concavenator would have fed on small to medium sized herbivores. Little is known about how it hunted. |
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| + | [[Image:Concavenator corcovatus thermo.jpg|thumb|right|Illustration of ''Concavenator'' using its hump as a hypothetical thermoregulatory device]] |
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| + | [[Image:Concavenator digsite.jpg|thumb|The digsite in 2002 before excavation]] |
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| + | Some amount of skepticism exists among experts about the validity of the interpretation that the ulna bumps represent quill knobs, though a more detailed analysis has not yet been published. [[Darren Naish]] of the blog Tetrapod Zoology speculates that the bumps would have been unusually far up and irregularly spaced for quill knobs. He additionally pointed out that many animals have similar structures along intermuscular lines that act as tendon attachment points among other things.<ref>Naish, D. (2010). [http://scienceblogs.com/tetrapodzoology/2010/09/concavenator_incredible_allosauroid.php ''Concavenator'': an incredible allosauroid with a weird sail (or hump)... and proto-feathers?]. Tetrapod Zoology, September 9, 2010.</ref> This dissent has been supported by Christian Foth and others.<ref>{{cite journal |year=2014 |title=New specimen of ''Archaeopteryx'' provides insights into the evolution of pennaceous feathers |journal=Nature |volume=511 |issue= 7507|pages=79–82 |url=http://www.nature.com/nature/journal/v511/n7507/full/nature13467.html |doi=10.1038/nature13467 |author= Christian Foth, Helmut Tischlinger, Oliver W. M. Rauhut}}</ref> |
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| + | ==Classification== |
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| − | IT HAS A SHARK FIN! |
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| + | The following cladogram after Novas ''et al.'', 2013, shows its within Carcharodontosauridae.<ref name="sciencedirect.com">{{cite journal | doi = 10.1016/j.cretres.2013.04.001 }}</ref> |
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| + | {{clade| style=font-size:100%;line-height:80% |
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| + | |1={{clade |
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| + | |1=''[[Allosaurus]]'' |
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| + | |label2='''Carcharodontosauridae''' |
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| + | |2={{clade |
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| + | |1=''[[Neovenator]]'' |
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| + | |2=''[[Eocarcharia]]'' |
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| + | |3='''''Concavenator''''' |
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| + | |4={{clade |
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| + | |1=''[[Acrocanthosaurus]]'' |
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| + | |2={{clade |
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| + | |1=''[[Shaochilong]]'' |
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| + | |label2=Carcharodontosaurinae |
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| + | |2={{clade |
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| + | |1=''[[Carcharodontosaurus]]'' |
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| + | |label2=Giganotosaurini |
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| + | |2={{clade |
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| + | |1=''[[Tyrannotitan]]'' |
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| + | |2={{clade |
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| + | |1=''[[Mapusaurus]]'' |
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| + | |2=''[[Giganotosaurus]]'' }} }} }} }} }} }} }} }} |
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| + | == See also == |
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| − | [[File:Zebu02.jpg|thumb|left|284px|The Zebu, a cow with a similar hump to what Concavenator may have had.]][[File:Camel2.jpg|thumb|306px|The camel's hump tends to be in the same place as that of Concavenator.]] |
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| + | *''[[Becklespinax]]'' |
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| + | |||
| + | ==References== |
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| + | {{Reflist|group=""|refs= |
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| + | <ref name="refname1" group="">Laursen, L. (2010). "[http://www.nature.com/news/2010/100908/full/news.2010.455.html Crested dinosaur pushes back dawn of feathers]." ''Nature News'', 8-Sept-2010. Accessed online 9-Sept-2010.</ref> |
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| + | <ref name="refname3" group="">Rivera, A. (2010). "[http://www.elpais.com/articulo/sociedad/Descubierto/Cuenca/dinosaurio/carnivoro/especie/desconocida/ahora/elpepusoc/20100908elpepusoc_6/Tes Descubierto en Cuenca un dinosaurio carnívoro de una especie desconocida hasta ahora]." ''El Pais.com'', 8-Sept-2010. Accessed online 9-Sept-2010.</ref> |
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| + | }} |
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| + | |||
| + | ==External links== |
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| + | *[http://www.nature.com/nature/journal/v467/n7312/images/nature09181-f4.2.jpg ''Concavenator'' arm bones, with quill knob-like structures visible]. |
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[[Category:Cretaceous]] |
[[Category:Cretaceous]] |
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[[Category:Dinosaurs]] |
[[Category:Dinosaurs]] |
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Latest revision as of 19:54, 6 November 2018
Concavenator is a genus of theropod dinosaur that lived approximately 130 million years ago during the early Cretaceous period (Barremian stage). The type species is C. corcovatus; Concavenator corcovatus means "hump backed hunter from Cuenca".[1] The fossil was discovered in the Las Hoyas fossil site of Spain by paleontologists José Luis Sanz, Francisco Ortega and Fernando Escaso from the Autonomous University of Madrid[2] and the National University of Distance Learning.[1]
Description
Fernando Escaso, Francisco Ortega, and José Luis Sanz working on Concavenator
Size compared to a human.
Concavenator was a medium-sized (roughly 6 meters (20 feet) long) primitive carcharodontosaurian dinosaur possessing several unique features. Two extremely tall vertebrae in front of the hips formed a tall but narrow and pointed crest (possibly supporting a hump) on the dinosaur's back.[3] The function of such crests is currently unknown. Paleontologist Roger Benson from Cambridge University speculated that one possibility is that "it is analogous to head-crests used in visual displays", but the Spanish scientists who discovered it noted it could also be a thermal regulator.[1]
Additionally, the forelimb (ulna) of Concavenator preserved evidence of what may be quill knobs or homologous structures, an anatomical feature so far known only in animals with large, quilled feathers on the forelimb.[3]
Feathers and scales
Restoration showing hypothetical integument
Concavenator had structures resembling quill knobs on its forearm, a feature known only in birds and other feathered theropods, such as Velociraptor. Quill knobs are created by ligaments which attach to the feather follicle, and since scales do not form from follicles, the authors ruled out the possibility that they could indicate the presence of long display scales on the arm. Instead, the knobs probably anchored simple, hollow, quill-like structures. Such structures are known both in coelurosaurs such as Dilong and in some ornithischians like Tianyulong and Psittacosaurus. If the ornithischian quills are homologous with bird feathers, their presence in an allosauroid like Concavenator would be expected.[3] However, if ornithischian quills are not related to feathers, the presence of these structures in Concavenator would show that feathers had begun to appear in earlier, more primitive forms than coelurosaurs. Feathers or related structures would then likely be present in the first members of the clade Neotetanurae, which lived in the Middle Jurassic. No impressions of any kind of integument were found near the arm, although extensive scale impressions were preserved on other portions of the body, including broad, rectangular scales on the underside of the tail, bird-like scutes on the feet, and plantar pads on the undersides of the feet.[3]
Illustration of Concavenator using its hump as a hypothetical thermoregulatory device
The digsite in 2002 before excavation
Some amount of skepticism exists among experts about the validity of the interpretation that the ulna bumps represent quill knobs, though a more detailed analysis has not yet been published. Darren Naish of the blog Tetrapod Zoology speculates that the bumps would have been unusually far up and irregularly spaced for quill knobs. He additionally pointed out that many animals have similar structures along intermuscular lines that act as tendon attachment points among other things.[4] This dissent has been supported by Christian Foth and others.[5]
Classification
The following cladogram after Novas et al., 2013, shows its within Carcharodontosauridae.[6]
Template:Clade
See also
- Becklespinax
References
- ↑ 1.0 1.1 1.2 Cite error: Invalid
<ref>tag; no text was provided for refs namedrefname1 - ↑ Cite error: Invalid
<ref>tag; no text was provided for refs namedrefname3 - ↑ 3.0 3.1 3.2 3.3 Template:Cite journal
- ↑ Naish, D. (2010). Concavenator: an incredible allosauroid with a weird sail (or hump)... and proto-feathers?. Tetrapod Zoology, September 9, 2010.
- ↑ Template:Cite journal
- ↑ Template:Cite journal