Massospondylus and Kjell Johansson (table tennis): Difference between pages

From Wikipedia, the free encyclopedia
(Difference between pages)
Content deleted Content added
VisualWikitext
m Reverted edits by 205.127.196.32 to last version by J.delanoy (HG)
 
Zorrobot (talk | contribs)
142,590 edits
m robot Adding: de, es, fr, ja, ko, no, pl
 
Line 1: Line 1:
'''Kjell Johansson''' is the name of:
{{Taxobox
| name = ''Massospondylus''
| fossil_range = [[Early Jurassic]]
| image = Massospondylus BW.jpg
| image_caption = This artist's impression of ''Massospondylus'' depicts the animal as bipedal.
| image_width = 200px
| regnum = [[Animal]]ia
| phylum = [[Chordate|Chordata]]
| classis = [[Reptile|Sauropsida]]
| superordo = [[Dinosaur]]ia
| ordo = [[Saurischia]]
| subordo = [[Sauropodomorpha]]
| infraordo = [[Prosauropoda]]
| familia = [[Massospondylidae]]
| genus = '''''Massospondylus'''''
| genus_authority = [[Richard Owen|Owen]], 1854
| subdivision_ranks = [[Species]]
| subdivision =
'''''M. carinatus''''' <small>Owen, 1854 ([[Type species|type]])</small>
| synonyms=
*?''[[Aetonyx]]'' <small>[[Robert Broom|Broom]], 1911</small>
*?''Aristosaurus'' <small>Hoepen, 1920</small>
*?''Dromicosaurus'' <small>Hoepen, 1920</small>
*?''Gryponyx'' <small>Broom, 1912</small>
*?''[[Gyposaurus]]'' <small>Broom, 1911</small>
*?''Hortalotarsus'' <small>[[Harry Seeley|Seeley]], 1894</small>
*?''Leptospondylus'' <small>[[Richard Owen|Owen]], 1895</small>
*?''Pachyspondylus'' <small>Owen, 1854</small>
}}
'''''Massospondylus''''' ({{pronEng|ˌmæsoʊˈspɒndɨləs}}, from [[Ancient Greek|Greek]], {{polytonic|[[wikt:μάσσων|μάσσων]]}} (massōn, "longer") and {{polytonic|[[wikt:σπόνδυλος|σπόνδυλος]]}} (spondylos, "vertebra")) is a [[genus]] of [[prosauropoda|prosauropod]] [[dinosaur]] from the early [[Jurassic]] [[Period (geology)|Period]] ([[Hettangian]] to [[Pliensbachian]] [[faunal stage|ages]], ca. 200–183&nbsp;[[annum|million years ago]]). It was described by Sir [[Richard Owen]] in 1854 from remains found in [[South Africa]], and is thus one of the first dinosaurs to have been named. Fossils have since been found at other locations in South Africa, [[Lesotho]], and [[Zimbabwe]]. Further material from [[Arizona]]'s [[Kayenta Formation]], [[India]], and [[Argentina]] has been assigned to this genus, but may not belong to ''Massospondylus''.


*[[Kjell Johansson (table tennis)]]
The [[type species|type]], and only universally recognized, species, is ''M. carinatus'', although six other species have been named during the past 150&nbsp;years. Prosauropod [[systematics]] have undergone numerous revisions during the last several years, and many scientists disagree where exactly ''Massospondylus'' lies on the dinosaur evolutionary tree. The family name [[Massospondylidae]] was once coined for the genus, but because knowledge of prosauropod relationships is in a state of flux, it is unclear which other dinosaurs—if any—belong in a natural grouping of massospondylids; several 2007 papers support the family's validity.
*[[Kjell Johansson (writer)]]
*[[Kjell Johansson (tennis player)]]
*[[Kjell Johansson (politician)]]


{{hndis|name=Johansson, Kjell}}
Although ''Massospondylus'' was long depicted as [[quadruped]]al, a 2007 study found it to be [[bipedalism|bipedal]]. It was probably a plant eater ([[Herbivory|herbivore]]), although it is speculated that the prosauropods may have been [[Omnivore|omnivorous]]. This animal, 4–6&nbsp;[[metre|meters]] (13–20&nbsp;[[foot (length)|feet]]) long, had a long neck and tail, with a small head and slender body. On each of its forefeet, it bore a sharp thumb claw that was used in defense or feeding. Recent studies indicate ''Massospondylus'' grew steadily throughout its lifespan, possessed [[air sac]]s similar to those of birds, and may have cared for its young.


[[de:Johansson]]
==Description==
[[es:Johansson]]
''Massospondylus'' was a mid-sized [[prosauropoda|prosauropod]] that was around 4&nbsp;meters (13&nbsp;ft) in length<ref name=DL83>{{cite book |last=Lambert |first=David |coauthors=and the Diagram Group |title=A Field Guide to Dinosaurs |year=1983 |publisher=Avon Books |location=New York |isbn=0-380-83519-3 |pages=p. 103}}</ref><ref name=DL90>{{cite book |last=Lambert |first=David |coauthors=and the Diagram Group |title=The Dinosaur Data Book |year=1990 |publisher=Avon Books |location=New York |isbn=0-380-75896-3 |pages=p. 75}}</ref><ref name="Seebacher01">{{cite journal| last =Seebacher| first =Frank| title =A new method to calculate allometric length-mass relationships of dinosaurs| journal =Journal of Vertebrate Paleontology| volume =21| issue =1| pages =51–60| year =2001|doi=}}</ref> and weighed approximately 135&nbsp;kilograms (300&nbsp;lb),<ref name="Seebacher01"/> although a few sources have estimated its length at up to 6&nbsp;meters (20&nbsp;ft).<ref name="LessemGlut">{{cite book|title=The Dinosaur Society Dinosaur Encyclopedia|year=1993|chapter=Massospondylus |last=Lessem |first=Don |coauthors=[[Donald F. Glut]]|publisher=Random House |pages=p. 295|isbn= 0-679-41770-2}}</ref><ref name=DFG00>{{cite book |chapter=Massospondylus |last=Glut |first=Donald F. |title=Dinosaurs: The Encyclopedia: Supplement One |year=2000 |publisher=McFarland & Co |location=Jefferson, North Carolina |pages=258 |isbn=0-7864-0591-0}}</ref> Although long assumed to have been [[quadruped]]al, a 2007 anatomical study of the forelimbs has questioned this, arguing that their range of motion precluded effective habitual quadrupedal gait. The study also ruled out the possibility of "knuckle-walking" and other forms of locomotion that would avoid the issue of the limited ability of ''Massospondylus'' to [[pronation|pronate]] its hands. Although its mass suggests a quadrupedal nature, it would have been restricted to its hind legs for locomotion.<ref name ="Bon07">{{cite book|last=,| first=Matthew |coauthors= Phil Senter |year=2007 |chapter=Were the basal sauropodomorph dinosaurs ''Plateosaurus'' and ''Massospondylus'' habitual quadrupeds? |editor=Paul M. Barrett & D. J. Batten (eds.) |title=Evolution and Palaeobiology of Early Sauropodomorph Dinosaurs|series=Special Papers in Palaeontology '''77''' |pages=139–155 |location=London |publisher=The Palaeontological Association |isbn=978-1-4051-6933-2}}</ref>
[[fr:Johansson]]
[[Image:Massospondylus 1 NHM2.jpg|250px|thumb|left|A mounted ''Massospondylus'' skeleton at the [[Natural History Museum]], [[London]], showing an outdated pre-2007 pose]]
[[ko:요한손]]

[[ja:ヨハンソン]]
''Massospondylus'' was a typical prosauropod in most other respects. It possessed a slender body and long neck, with around nine long cervical (neck) vertebrae, 13 dorsal (back) vertebrae, three sacral (hip) vertebrae, and at least 40 caudal (tail) vertebrae. The [[pubis (bone)|pubis]] faced forward, as with most [[saurischia]]ns. It had a slighter build than that of ''[[Plateosaurus]]'', an otherwise similar prosauropod dinosaur.<ref name="Dinosauria"/> A recent discovery shows that ''Massospondylus'' possessed well-developed [[clavicle]]s, joined in a [[furcula]]-like arrangement, suggesting both that it had immobile [[scapula|shoulder blades]] and that clavicles were not rudimentary and nonfunctional in those dinosaurs that did not have true furculae. This discovery also indicates that the furcula of [[bird]]s is derived from clavicles.<ref name=YV05>{{cite journal |last=Yates |first=Adam M. |coauthors=and Vasconcelos, Cecilio C. |year=2005 |title=Furcula-like clavicles in the prosauropod dinosaur ''Massospondylus'' |journal=Journal of Vertebrate Paleontology |volume=25 |issue=2 |pages=466–468|doi=}}</ref>
[[no:Johansen]]

[[pl:Johansson]]
Like ''Plateosaurus'', it had five digits on each foot, with a large thumb claw used for feeding or defense against predators. The fourth and fifth digits of the forepaws were tiny, giving the forepaws a lopsided look. The 2007 study indicated that ''Massospondylus'' held its [[manus (zoology)|manus]] (hands) in a semi-supinated ("prayer-like") orientation, with the palmar surfaces facing one another; the wrist was never found rotated in articulated (still-connected) fossil specimens.<ref name="Bon07"/>
[[sv:Kjell Johansson]]

===Cranial anatomy===
[[Image:Massospondylus Skull Steveoc 86.png|thumb|300px|Above is a diagram of the skull of ''Massospondylus'', showing the various skull openings.]]

The small head of ''Massospondylus'' was approximately half the length of the [[femur]]. Numerous openings, or [[fenestrae]], in the skull reduced its weight and provided space for muscle attachment and sensory organs. These fenestrae were present in pairs, one on each side of the skull. At the front of the skull were two large, elliptical [[nostril|nares]]. The [[orbit (anatomy)|orbits]] were proportionally larger in ''Massospondylus'' than in related genera such as ''Plateosaurus''. The [[antorbital fenestra]]e, smaller than those seen in ''Plateosaurus'', were situated between the eyes and the nose. At the rear of the skull were two more pairs of [[temporal fenestra]]e: the [[infratemporal fenestra|lateral temporal fenestra]]e immediately behind the eye sockets and the supratemporal fenestrae on top of the skull. Small fenestrae also penetrated each [[mandible]].<ref name="Dinosauria"/> The shape of the skull is traditionally restored as wider and shorter than that of ''Plateosaurus'', but this appearance may be due just to differential crushing experienced by the various specimens.<ref name="Dinosauria"/> Some features of the skull are variable between individuals; for example, the thickness of the upper border of the orbit and the height of the posterior [[maxilla]]. These differences may be due to [[sexual dimorphism]]<ref name=GKR90>{{cite journal |last=Gow |first=Christoper E. |coauthors=J.W. Kitching and Michael K. Raath |year=1990 |title=Skulls of the prosauropod dinosaur ''Massospondylus carinatus'' Owen in the collections of the Bernard Price Institute for Palaeontological Research |journal=Palaeontologia Africana |volume=27 |pages=45–58}}</ref> or individual variation.<ref name=PMG97>{{cite journal |last=Galton |first=Peter M. |authorlink=Peter Galton |year=1997 |title=Comments on sexual dimorphism in the prosauropod dinosaur ''Plateosaurus engelhardti'' (Upper Triassic, Trossingen) |journal=Neues Jahrbuch für Geologie und Paläontologie, Monatshefte |volume=11 |pages=674–682}}</ref>

As with other prosauropods, it has been proposed that ''Massospondylus'' had cheeks. This theory was proposed because there are a few large holes for blood vessels on the surfaces of the jaw bones, unlike the numerous small holes present on the jaws of cheekless reptiles. The cheeks would have prevented food from spilling out when ''Massospondylus'' ate.<ref name="Dinosauria"/> Crompton and Attridge (1986) described skulls of ''Massospondylus'' as possessing pronounced [[malocclusion|overbite]]s and suggested the presence of a [[keratin|horny]] beak on the tip of the lower jaw to make up the difference in length and account for tooth wear on the teeth at the tip of the snout.<ref name=CA86>{{cite book |last=Crompton |first=A.W. |coauthors=John Attridge |year=1986 |chapter=Masticatory apparatus of the larger herbivores during Late Triassic and Early Jurassic times |editor=Kevin Padian (ed.) |title=The Beginning of the Age of Dinosaurs: Faunal Change Across the Triassic–Jurassic Boundary |location=New York |publisher=Cambridge University Press |pages=223–236 |isbn=0-521-36779-4 }}</ref> However, this was later shown to be a misinterpretation based on crushing in a top–bottom plane. Skulls not crushed in this orientation do not show an overbite.<ref name=GKR90/> There also seems to be some variation of tooth morphology based on the position of teeth in the jaw.<ref name="ageofdinosaursmassospondylus" /> The [[heterodont]]y present in ''Massospondylus'' is greater than that present in ''[[Plateosaurus]]'', although unsurprisingly not as pronounced as the specialization of teeth in ''[[Heterodontosaurus]]''.<ref name="ageofdinosaursmassospondylus" /> Teeth closer to the front of the snout had round cross-sections and tapered to points, unlike the back teeth, which were [[spatula]]te and had oval cross-sections.<ref name="Dinosauria"/><ref name="ageofdinosaursmassospondylus" />

==Discovery==
The first fossils of ''Massospondylus'' were described by [[paleontology|paleontologist]] Sir [[Richard Owen]] in 1854,<ref>Owen, Richard (1854). "Descriptive catalogue of the Fossil organic remains of Reptilia and Pisces contained in the Museum of the Royal College of Surgeons of England." London p. 1–184 {{OCLC|14825172}}</ref> the name having been derived from the [[Ancient Greek|Greek]] terms ''masson''/μάσσων 'longer'<ref name="Creisler">{{cite web| last =Creisler| first =Ben| title =Dinosauria Translation and Pronunciation Guide| publisher =Dinosauria.com| year =2003| url =http://www.dinosauria.com/dml/names/dinom.htm| accessdate =2007-11-23}}</ref> and ''sphondylos''/σφονδυλος 'vertebra'.<ref name="Liddell 1980">{{cite book | last = Liddell| first=Henry George |authorlink=Henry Liddell |coauthors= [[Robert Scott (philologist)|Robert Scott]] | year = 1980 | title = [[A Greek-English Lexicon]] (Abridged Edition) | publisher = Oxford University Press | location = Oxford | isbn= 0-19-910207-4}}</ref> These fossils were found in 1853 by J. M. Orpen in the [[Upper Elliot Formation]] at [[Harrismith]], [[South Africa]]. Included among the remains were vertebrae from the neck, back, and tail; a shoulder blade; a [[humerus]]; a partial pelvis; a femur; a [[tibia]]; and bones of the hands and feet. The original [[holotype]] material was part of the [[Royal College of Surgeons of England|Royal College of Surgeons]] collection in London and was destroyed in [[World War II]]; only casts remain.<ref name=DFG97>{{cite book|chapter=Massospondylus |last=Glut |first=Donald F. |title=Dinosaurs: The Encyclopedia |year=1997 |publisher=McFarland & Co |location=Jefferson, North Carolina |pages=581–586 |isbn=0-89950-917-7}}</ref> Possible ''Massospondylus'' remains have been found in the Upper Elliot Formation, the [[Clarens Formation]], and the [[Bushveld Sandstone]] of South Africa and [[Lesotho]]; the [[Forest Sandstone]] and the [[Upper Karroo Sandstone]] of [[Zimbabwe]]; the Cañon del Colorado Formation or [[El Tranquilo Formation]] of [[Argentina]];<!--Dino II says Cañon del Colorado, Aragosaurus.com says El Tranquilo, both using Martinez as the base ref; go figure--> and the [[Kayenta Formation]] of [[Arizona]]. These remains consist of at least 80 partial skeletons and four skulls, representing both juveniles and adults.<ref name="Dinosauria"/>

The reports of ''Massospondylus'' from Argentina include several partial skeletons, including at least one skull, from the [[Early Jurassic|Lower Jurassic]] Cañon del Colorado Formation of [[San Juan, Argentina|San Juan]], Argentina.<ref name="Dinosauria"/> The report of ''Massospondylus'' from Arizona's Kayenta Formation is based on a skull described in 1985. The skull of the Kayenta specimen from Arizona is 25% larger than the largest skull from any African specimen.<ref name="ageofdinosaursmassospondylus">"Massospondylus." In: Dodson, Peter & Britt, Brooks & Carpenter, Kenneth & Forster, Catherine A. & Gillette, David D. & Norell, Mark A. & Olshevsky, George & Parrish, J. Michael & Weishampel, David B. ''The Age of Dinosaurs''. Publications International, LTD. p. 39. ISBN 0-7853-0443-6.</ref> The Kayenta specimen possesses four teeth in the [[premaxilla]] and sixteen in the [[maxilla]]. Uniquely among dinosaurs, it also had tiny, one-[[millimetre|millimeter]]-(0.04&nbsp;[[inch|in]]-) long palatal teeth.<ref name="Attridgeetal85">{{cite journal| last =Attridge| first =J.| coauthors = A.W. Crompton and Farish A. Jenkins, Jr. | title =The southern Liassic prosauropod ''Massospondylus'' discovered in North America| journal =Journal of Vertebrate Paleontology| volume =5| issue =2| pages =128–132| year =1985}}</ref> Recent restudy of African ''Massospondylus'' skulls, however, indicates that the Kayenta specimen does not pertain to ''Massospondylus''.<ref name=SRHR04>{{cite journal |last=Sues |first=H.-D. |coauthors=R.R. Reisz, S. Hinic and M.A. Raath |year=2004 |title=On the skull of ''Massospondylus carinatus'' Owen, 1854 (Dinosauria: Sauropodomorpha) from the Elliot and Clarens formations (Lower Jurassic) of South Africa |journal=Annals of Carnegie Museum |volume=73 |issue=4 |pages=239–257}}</ref>

===Species===
Many species have been named, although most are no longer considered valid. ''M. carinatus'', named by Richard Owen, is the [[type species]].<ref name="PaleobiologyDB">{{cite web| title =Massospondylus| publisher =The Paleobiology Database| year =2007| url =http://paleodb.org/cgi-bin/bridge.pl?action=checkTaxonInfo&taxon_no=38642&is_real_user=1 | accessdate =2007-11-03}}</ref> Other named species include: ''M. browni'' ([[Harry Seeley|Seeley]], 1895),<ref name="Seeley1895">{{cite journal| last =Seeley| first =H.G.| title =On the type of the genus ''Massospondylus'' and on some Vertebrae and limb-bone of ''M. (?) browni''| journal =Annals and Magazine of Natural History| volume =15| issue =| pages =102–125| year =1895}}</ref> ''M. harriesi'' ([[Robert Broom|Broom]] 1911),<ref name="Broom11">{{cite journal| last =Broom| first =Robert| title =On the dinosaurs of the Stormberg, South Africa| journal =Annals of the South African Museum| volume =7| issue =4| pages =291–308| year =1911}}</ref> ''M. hislopi'' ([[Richard Lydekker|Lydekker]], 1890),<ref name="Lydekker">{{cite journal| last =Lydekker| first =Richard| coauthors =| title =Note on certain vertebrate remains from the Nagpur district| journal =Records of the Geological Survey of India| volume =23| issue =1| pages =21–24| year=1890}}</ref> ''M. huenei'' (Cooper, 1981),<ref name="Cooper">{{cite journal| last =Cooper| first =M.R.| title =The prosauropod dinosaur ''Massospondylus carinatus'' Owen from Zimbabwe: its biology, mode of life and phylogenetic significance| journal =Occasional Papers of the National Museums and Monuments of Rhodesia, Series B, Natural Sciences| volume =6| issue =10| pages =689–840| year=1980}}</ref> ''M. rawesi'' (Lydekker, 1890),<ref name="Lydekker"/> and ''M. schwarzi'' ([[Sydney H. Haughton|Haughton]], 1924).<ref name="Haughton1924">{{cite journal| last =Haughton| first =Sydney H. |title =The fauna and stratigraphy of the Stormberg Series| journal =Annals of the South African Museum| volume =12 |pages =323–497| year=1924 }}</ref>

''M. browni'', ''M. harriesi'', and ''M. schwarzi'' were all found in the Upper Elliot Formation of [[Cape Province]], South Africa. All three are based on fragmentary material, and were regarded as [[nomen dubium|indeterminate]] in the most recent review.<ref name="Dinosauria"/> ''M. browni'' is based on two [[neck|cervical]], two back, and three [[tail|caudal]] [[vertebra]]e and miscellaneous hind limb elements.<ref name="Seeley1895"/> ''M. harriesi'' is known from a forelimb.<ref name="Broom11"/> ''M. schwarzi'' is known from an incomplete hind limb and [[sacrum]].<ref name="Haughton1924"/> ''M. hislopi'' and ''M. rawesi'' were named from fossils found in [[India]].<ref name="Lydekker"/> ''M. hislopi'' is based on vertebrae from the [[Late Triassic|Upper Triassic]] [[Maleri Formation]] of [[Andhra Pradesh]], whereas ''M. rawesi'' is based on a tooth from the [[Late Cretaceous|Upper Cretaceous]] Takli Formation of [[Maharashtra]].<ref name=DBW90>{{cite book |last=Weishampel |first=David B. |authorlink=David B. Weishampel |chapter=Dinosaur distribution |editor=David B. Weishampel, Peter Dodson and Halszka Osmólska (eds.)|title=The Dinosauria |edition=1st ed. |year=1990 |publisher=University of California Press |location=Berkeley |isbn=0-520-06727-4 |pages=63–139 }}</ref> ''M. hislopi'' was tentatively retained as an indeterminate sauropodomorph in the latest review,<ref name="Dinosauria"/> but ''M. rawesi'' may be a [[Theropoda|theropod]]<ref name=RM90>Molnar, R.E. (1990). Problematic Theropoda: "Carnosaurs". In Weishampel & ''als'': ''The Dinosauria'' (1st ed.), pp. 306–317.</ref> or nondinosaur.<ref name=DFG97/> ''M. huenei'' is a combination derived by Cooper for ''[[Lufengosaurus|Lufengosaurus huenei]]'', as he considered ''Lufengosaurus'' and ''Massospondylus'' to be synonyms.<ref name="Cooper"/> This synonymy is no longer accepted.<ref name="Dinosauria"/>

===Dubious names===
Several dinosaurs are often considered synonymous with ''Massospondylus''. These include ''Aristosaurus'', ''Dromicosaurus'', ''Gryponyx'', ''Hortalotarsus'', ''Leptospondylus'', and ''Pachyspondylus'', which are dubious names of little scientific value.<ref name="Cooper"/> ''Hortalotarsus skirtopodus'' was named by [[Harry Seeley]] in 1894. The fossils consist of partial leg bones. The following year, Richard Owen named a few fossil vertebrae ''Leptospondylus capensis'' and ''Pachyspondylus orpenii''. These fragmentary fossils were later destroyed in World War II. ''Aristosaurus erectus'' was named by E.C.N. van Hoepen in 1920 based on a nearly complete skeleton. Hoepen also named ''Dromicosaurus gracilis'', which consisted of a partial skeleton. ''Gryponyx taylori'' was named by [[Sidney H. Haughton]] in 1924. It consists of hip bones. All of the above fossils come from the Hettangian or Sinemurian faunal stages of South Africa, where ''Massospondylus'' has been found.<ref name="Tweet">{{cite web| last =Tweet| first =Justin| title =Sauropodomorpha| work =Thescelosaurus!| year =2007| url =http://www.users.qwest.net/~jstweet1/sauropodomorpha.htm| accessdate =2007-12-16}}</ref><ref name=WETAL04>{{cite book |last=Weishampel |first=David B. |coauthors=Paul M. Barrett, Rodolfo Coria, A., Jean Le Loeuff, Zhao Xijin Xu Xing, Ashok Sahni, Elizabeth M.P. Gomani and Christopher R. Noto|chapter=Dinosaur Distribution |editor=David B. Weishampel, Peter Dodson and Halszka Osmólska (eds.)|title=The Dinosauria |edition=2nd ed. |year=2004|publisher=University of California Press |location=Berkeley |isbn=0-520-24209-2 |pages=pp. 517–606 }}</ref> Under the rules of zoological nomenclature, these names are [[synonym (taxonomy)|junior synonym]]s. They were named after ''Massospondylus'' was described in a scientific paper; the name ''Massospondylus'' thus takes priority.

==Classification==
{|style="margin-left: 1em;; margin-bottom: 0.5em; width: 248px; border: #99B3FF solid 1px; background-color: #FFFFFF; color: #000000; float: right; "
|{{clade|style=font-size:75%
|label1=&nbsp;[[Plateosauria]]&nbsp;
|1={{clade
|label1=&nbsp;[[Plateosauridae]]&nbsp;
|1={{clade
|1=''[[Unaysaurus]]''
|2=''[[Plateosaurus]]''
}}
|label2=&nbsp;[[Massopoda]]&nbsp;
|2={{clade
|label1=[[Riojasauridae]]&nbsp;
|1={{clade
|1=''[[Riojasaurus]]''
|2=''[[Eucnemesaurus]]''
}}
|label2=&nbsp;(unnamed)&nbsp;
|2={{clade
|label1=&nbsp;[[Massospondylidae]]&nbsp;
|1={{clade
|1=''[[Massospondylus]]''&nbsp;
|label2=&nbsp;(unnamed)&nbsp;
|2={{clade
|1=''[[Coloradisaurus]]''&nbsp;
|2=''[[Lufengosaurus]]''&nbsp;
}}
}}
|label2=&nbsp;(unnamed)&nbsp;
|2={{clade
|1=''[[Jingshanosaurus]]''
|2=[[Anchisauria]]
}}
}}
}}
}}
}}
<center><small>Basal sauropodomorph phylogeny simplified after Yates, 2007.<ref name="Yates"/> In this review, ''Massospondylus'' is shown as closely related to ''Lufengosaurus'' and ''Coloradisaurus''. This is only one of many proposed cladograms for basal sauropodomorphs.</small></center>
|}
''Massospondylus'' is a [[prosauropoda|prosauropod]], a grouping of early [[saurischia]]n dinosaurs that lived during the Triassic and Jurassic, but which had died out by the end of the Jurassic. Other members of the group include ''[[Plateosaurus]]'',<ref name="Dinosauria">Galton, P.M. and Upchurch, P. (2004). "Prosauropoda". Weishampel & ''als'': ''The Dinosauria'' (2nd edition), pp. 232–258.</ref> ''[[Yunnanosaurus]]'',<ref name="Dinosauria"/> and ''[[Riojasaurus]]''.<ref name="Galtonetal05">{{cite book |last=Galton |first=P.M |coauthor=J. Van Heerden and A.M. Yates |chapter=Postcranial anatomy of referred specimens of the sauropodomorph dinosaur ''Melanorosaurus'' from the Upper Triassic of South Africa |editor=Virginia Tidwell and Kenneth Carpenter (eds.) |year=2005 |title=Thunder-Lizards: The Sauropodomorph Dinosaurs |location=Bloomington |publisher=Indiana University Press |isbn=0-253-34542-1 |pages=pp. 1–37}}</ref> Basal sauropodomorph systematics continue to undergo revision, and many genera once considered classic prosauropods have recently been removed from the group in [[phylogenetic nomenclature]], on the grounds that their inclusion would not constitute a [[clade]] (a natural grouping containing all descendants of a single common ancestor). Exactly which animals constitute a [[monophyly|monophyletic]] (natural grouping) of prosauropods is unclear. Yates and [[James Kitching|Kitching]] (2003) published a clade consisting of ''Riojasaurus'', ''Plateosaurus'', ''[[Coloradisaurus]]'', ''Massospondylus'', and ''[[Lufengosaurus]]''.<ref name="YatesKitching03">{{cite journal |last=Yates |first=Adam M. |coauthors=James W. Kitching |month= |year=2003 |title=The earliest known sauropod dinosaur and the first steps towards sauropod locomotion |journal=Proceedings of the Royal Society B |volume=270 |issue=1525 |pages=1753–1758 |doi=10.1098/rspb.2003.2417}}</ref> Galton and Upchurch (2004) included ''[[Ammosaurus]]'', ''[[Anchisaurus]]'', ''[[Azendohsaurus]]'', ''[[Camelotia]]'', ''Coloradisaurus'', ''[[Euskelosaurus]]'', ''[[Jingshanosaurus]]'', ''[[Lessemsaurus]]'', ''Lufengosaurus'', ''Massospondylus'', ''[[Melanorosaurus]]'', ''[[Mussaurus]]'', ''Plateosaurus'', ''Riojasaurus'', ''[[Ruehleia]]'', ''[[Saturnalia (dinosaur)|Saturnalia]]'', ''[[Sellosaurus]]'', ''[[Thecodontosaurus]]'', ''[[Yimenosaurus]]'' and ''Yunnanosaurus'' in a monophyletic Prosauropoda.<ref name="Dinosauria"/> Wilson (2005) considered ''Massospondylus'', ''Jingshanosaurus'', ''Plateosaurus'', and ''Lufengosaurus'' a natural group, with ''[[Blikanasaurus]]'' and ''[[Antetonitrus]]'' possible sauropods.<ref name="Wilson">{{cite book| last =Wilson| first =Jeffrey A.| coauthors =Curry Rogers, Kristina| title = The Sauropods: Evolution and Paleobiology| publisher =University of California Press| year =2005| location =Berkeley| pages =pp. 15–49 | isbn =978-0-520-24623-2 }}</ref> Bonnan and Yates (2007) considered ''Camelotia'', ''Blikanasaurus'' and ''Melanorosaurus'' possible sauropods.<ref name="BonnanYates07">Bonnan, Matthew F. and Adam M. Yates, "A new description of the forelimbs of the basal sauropodomorph ''Melanorosaurus'': implications for the evolution of pronation, manus shape and quadrupedalism in sauropod dinosaurs". In Barrett & Batten (eds.), ''Evolution and Palaeobiology'' (2007), pp. 157–168.</ref> Yates (2007) placed ''Antetonitrus'', ''Melanorosaurus'', and ''Blikanasaurus'' as basal sauropods and declined to use the term Prosauropoda, as he considered it synonymous with Plateosauridae. However, he did not rule out the possibility that a small group of prosauropods consisting of ''Plateosaurus'', ''Riojasaurus'', ''Massospondylus'' and their closest kin were monophyletic.<ref name="Yates">Yates, Adam M., "The first complete skull of the Triassic dinosaur ''Melanorosaurus'' Haughton (Sauropodomorpha: Anchisauria)". In Barrett & Batten (eds.), ''Evolution and Palaeobiology'' (2007), pp. 9–55.</ref>

''Massospondylus'' is the [[type genus]] of the proposed family [[Massospondylidae]], to which it gives its name. The Massospondylidae family may also include ''Yunnanosaurus'',<ref name="Sereno">{{cite journal| last =Sereno| first =Paul C.| title =The evolution of dinosaurs| journal =[[Science (journal)|Science]]| volume =284| issue =5423| pages =2137–2147 doi =10.1126/science.284.5423.2137| year =1999| pmid =10381873}}</ref> although Lu ''et al.'' (2007) placed ''Yunnanosaurus'' in its own family.<ref name="Luetal07">{{cite journal| last =Lu| first =J.| coauthors = T. Li, S. Zhong, Y. Azuma, M. Fujita, Z Dong and Q. Ji| title =New yunnanosaurid dinosaur (Dinosauria, Prosauropoda) From the Middle Jurassic Zhanghe Formation of Yuanmou, Yunnan province of China| journal =Memoir of the Fukui Prefectural Dinosaur Museum| volume =6| issue =| pages =1–15| year =2007}}</ref> Yates (2007) considered ''Massospondylus'', ''Coloradisaurus'', and ''Lufengosaurus'' massospondylids, with ''Yunnanosaurus'' in [[Anchisauria]].<ref name="Yates"/> Smith and Pol (2007) also found a Massospondylidae in their phylogenetic analysis, including ''Massospondylus'', ''Coloradisaurus'', and ''Lufengosaurus'', as well as their new genus, ''[[Glacialisaurus]]''.<ref name=SP07>{{cite journal |last=Smith |first=Nathan D. |coauthors= Diego Pol|year=2007 |title=Anatomy of a basal sauropodomorph dinosaur from the Early Jurassic Hanson Formation of Antarctica |journal=Acta Palaeontologica Polonica |volume=52 |issue=4 |pages=657–674 |url=http://www.app.pan.pl/acta52/app52-657.pdf |format=pdf }}</ref>

==Paleoecology==
The [[fauna]]s and [[flora]]s of the Early Jurassic were similar worldwide, with [[Pinophyta|conifer]]s adapted for hot weather becoming the common plants,<ref name=DAR89>{{cite book |last=Russell |first=Dale A. |authorlink=Dale Russell |title=An Odyssey in Time: Dinosaurs of North America|year=1989 |publisher=NorthWord Press |location=Minocqua, Wisconsin |isbn=1-55971-038-1 |pages=p. 45 }}</ref> and prosauropods and [[basal (phylogenetics)|basal]] [[Theropoda|theropod]]s the main constituents of a worldwide dinosaur fauna.<ref name=HCL04>Holtz, Thomas R., Jr., Ralph E. Chapman and Matthew C. Lamanna, "Mesozoic biogeography of Dinosauria". In Weishampel & ''als.'', ''The Dinosauria'' (2nd edition), pp. 627–642.</ref> The environment of early Jurassic southern Africa has been described as a desert.<ref name=GSP88>{{cite_book |last=Paul |first=Gregory S. |authorlink=Gregory S. Paul |year=1988 |title=Predatory Dinosaurs of the World |chapter=Coelophysis rhodesiensis |location=New York |publisher=Simon and Schuster |pages=pp. 262–265 |isbn=978-0-6716-1946-6}}</ref> African ''Massospondylus'' was a contemporary of early [[crocodylomorpha|crocodylomorphs]]; [[tritylodontidae|tritylodontid]] and [[trithelodontidae|trithelodontid]] [[Therapsida|therapsid]]s; [[morganucodon]]tid [[mammal]]s;<ref name="Dinosauria"/> and dinosaurs including the small theropod ''[[Megapnosaurus|Megapnosaurus rhodesiensis]]''; a species of ''[[Melanorosaurus]]'' (''M. thabanensis''); and several genera of early [[ornithischia]]ns, such as ''[[Lesothosaurus]]'' and the [[heterodontosauridae|heterodontosaurids]] ''[[Abrictosaurus]]'', ''[[Heterodontosaurus]]'', and ''[[Lycorhinus]]''.<ref name=WETAL04/>

It is not clear which carnivores may have preyed on ''Massospondylus''. Most of the theropods which have been discovered in rocks of Early Jurassic age in southern Africa, such as ''Megapnosaurus'', were smaller than mid-sized prosauropods like ''Massospondylus''. These smaller predators have been postulated as using fast slashing attacks to wear down prosauropods, which could have defended themselves with their large hand and foot claws.<ref name=GSP88/> The 6-meter-(20&nbsp;ft-) long <ref name="Smithetal">{{cite book |last=Smith |first=N.D. |coauthors=P.J. Makovicky, D. Pol, W.R. Hammer and P.J. Currie |chapter=The Dinosaurs of the Early Jurassic Hanson Formation of the Central Transantarctic Mountains: Phylogenetic Review and Synthesis |editor=Alan Cooper, Carol Raymond et ''als.'' (eds.) |year=2007 |title=Antarctica: A Keystone in a Changing World—Online Proceedings for the Tenth International Symposium on Antarctic Earth Sciences |location=Reston, Virginia |publisher=U.S. Geological Survey |isbn=1-411-31788-2 |url=http://pubs.usgs.gov/of/2007/1047/srp/srp003/of2007-1047srp003.pdf |doi=doi:10.3133/of2007-1047.srp003}}</ref> carnivorous theropod ''[[Dracovenator]]'' lived during the same period (Hettangian to Sinemurian stages) as ''Massospondylus'' and has also been found in the Elliot Formation of South Africa.<ref name="Yates0506">{{Cite journal| last =Yates| first =A.M.| title =A new theropod dinosaur from the Early Jurassic of South Africa and its implications for the early evolution of theropods| journal =Palaeontologia africana| volume =41| issue =| pages =105–122| year =2006}}</ref>

==Paleobiology==
As with all dinosaurs, much of the biology of ''Massospondylus'', including its behavior, coloration, and physiology, remains unknown. However, recent studies have allowed for informed speculation on subjects such as growth patterns,<ref name="Sanderklein"/> diet,<ref name="Weemsetal"/> posture,<ref name="Bon07"/> reproduction,<ref name="Reiszetal05"/> and respiration.<ref name="Wedel"/>

A 2007 study suggested that ''Massospondylus'' may have used its short arms in defense from predators ("defensive swats"), in intraspecies combat, or in feeding, although its arms were too short to reach its mouth. Scientists speculate that ''Massospondylus'' could have used its large [[thumb|pollex]] (thumb) claw in combat, to strip plant material from trees,<ref name ="Bon07"/> digging, or for grooming.<ref name="ageofdinosaursmassospondylus" />

===Growth===
A 2005 study indicated that ''Massospondylus''' sister taxon, ''Plateosaurus'', exhibited growth patterns affected by environmental factors. The study indicated that when food was plentiful, or when the climate was favorable, ''Plateosaurus'' exhibited accelerated growth. This pattern of growth is called "developmental plasticity". It is unseen in other dinosaurs, including ''Massospondylus'', despite the close relationship between ''Plateosaurus'' and ''Massospondylus''. The study indicated that ''Massospondylus'' grew along a specific growth trajectory with little variation in the growth rate and ultimate size of an individual.<ref name="Sanderklein">{{cite journal| last =Sander| first =P. Martin| coauthors = Nicole Klein| title =Developmental plasticity in the life history of a prosauropod dinosaur| journal =Science| volume =310| issue =5755| pages =1800–1802| year =2005| doi =10.1126/science.1120125| pmid =16357257}}</ref> Another study indicated that ''Massospondylus'' grew at a maximum rate of 34.6&nbsp;kg (76.3&nbsp;lb) per year and was still growing at around 15 years of age.<ref name="Ericksonetal">{{cite journal| last =Erickson| first =Gregory M.| coauthors =Kristina Curry Rogers and Scott A. Yerby| title =Dinosaurian growth patterns and rapid avian growth rates| journal =Nature| volume =412| issue =| pages =429–433| year =2001| doi =10.1038/35086558}}</ref>

===Diet===
Prosauropods such as ''Massospondylus'' may have been [[Herbivory|herbivorous]] or [[omnivore|omnivorous]]. As recently as the 1980s, paleontologists debated the possibility of [[carnivore|carnivory]] in prosauropods.<ref name="Cooper"/><ref name="Attridgeetal85"/> However, the hypothesis of carnivorous prosauropods has been discredited, and all recent studies favor a herbivorous or omnivorous lifestyle for these animals. Galton and Upchurch (2004) found that cranial characteristics (such as jaw articulation) of most prosauropods are closer to those of herbivorous reptiles than those of carnivorous ones, and the shape of the tooth [[Crown (tooth)|crown]] is similar to those of modern herbivorous or omnivorous [[iguana]]s. The maximum width of the crown was greater than that of the root, resulting in a cutting edge similar to those of extant herbivorous or omnivorous reptiles.<ref name="Dinosauria"/> Barrett (2000) proposed that prosauropods supplemented their herbivorous diets with small prey or [[carrion]].<ref name="Barrett">{{cite book |last=Barrett |first=P.M. |chapter=Prosauropod dinosaurs and iguanas: Speculations on the diets of extinct reptiles |editor=Hans-Dieter Sues |year=2000 |title=Evolution of Herbivory in Terrestrial Vertebrates: Perspectives from the Fossil Record |location=Cambridge |publisher=Cambridge University Press |isbn=978-0-521-59449-3 |pages=pp. 42–78}}</ref> [[Gastrolith]]s (gizzard stones) have been found in association with ''Massospondylus'' fossils in South Africa,<ref name="ageofdinosaursmassospondylus" />, and with a ''Massospondylus''-like animal from the [[Late Triassic]] of [[Virginia]].<ref name="Weemsetal">{{cite journal| last =Weems| first =Robert E.| coauthors = Michelle J. Culp and Oliver Wings| title =Evidence for Prosauropod Dinosaur Gastroliths in the Bull Run Formation (Upper Triassic, Norian) of Virginia| journal =Ichnos| volume =13| issue =3–4| pages =271–295| year =2007| doi =10.1080/10420940601050030}}</ref> ''Massospondylus'' swallowed these stones to aid in digestion;<ref name="ageofdinosaursmassospondylus" /> muscular contractions in the creature's gizzard would have pulverized swallowed plant material, compensating for its inability to chew.

===Reproduction===
[[Image:Massospondylus baby BW.jpg|thumb|200px|right|An artist's depiction of a juvenile ''Massospondylus'', shown here as a quadruped]]

In 1977, seven 190-million-year-old ''Massospondylus'' eggs were found in [[Golden Gate Highlands National Park]] in [[South Africa]] by [[James Kitching]], who identified them as most likely belonging to ''Massospondylus''. It was nearly 30 years before extraction was started on the fossils of the 15-[[centimetre|centimeter]]- (6&nbsp;in-) long embryos. They remain the oldest dinosaur embryos ever found. Notably, the near-hatchlings had no teeth, suggesting they had no way of feeding themselves. Based on the lack of teeth and the animal's body proportions, scientists speculate that postnatal care might have been necessary. The four legs of the near-hatchlings were of equal length, indicating that newly hatched ''Massospondylus'' were quadrupedal.<ref name="Reiszetal05">{{cite journal| last =Reisz| first =Robert R.| coauthors =Diane Scott, Hans-Dieter Sues, David C. Evans, Michael A. Raath| title =Embryos of an Early Jurassic prosauropod dinosaur and their evolutionary significance| journal =Science| volume =309| issue =5735| pages =761–764| year =2005| doi =10.1126/science.1114942| pmid =16051793}}</ref> The skull and eyes were proportionately oversized when compared to adults, as is common in other very young vertebrates, although the skulls of juveniles were taller and more narrow as well.<ref name="ageofdinosaursmassospondylus" /> The quadrupedality of the hatchlings suggests that the quadrupedal posture of later [[sauropod]]s may have evolved from retention of juvenile characteristics in adult animals, an evolutionary phenomenon known as [[pedomorphosis]].<ref name="Reiszetal05"/>

===Respiratory system===
Many [[saurischia]]n dinosaurs possessed vertebrae and ribs that contained hollowed-out cavities (pneumatic [[Foramina of skull|foramina]]), which reduced the weight of the bones and may have served as a basic 'flow-through ventilation' system similar to that of modern birds. In such a system, the neck vertebrae and ribs are hollowed out by the cervical air sac; the upper back vertebrae, by the [[lung]]; and the lower back and [[sacrum|sacral]] (hip) vertebrae, by the abdominal air sac. These organs constitute a complex and very efficient method of respiration.<ref name=oconnorclaessens2006>{{cite_journal |last=O'Connor |first=Patrick M. |coauthors= Leon P.A.M. Claessens|year=2006 |title=Basic avian pulmonary design and flow-through ventilation in non-avian theropod dinosaurs |journal=Nature |volume=436 |issue=7048 |pages=253–256 |doi=10.1038/nature03716}}</ref> Prosauropods are the only major group of saurischians without an extensive system of pneumatic foramina. Although possible pneumatic indentations have been found in ''Plateosaurus'' and ''Thecodontosaurus'', the indentations were very small. One study in 2007 concluded that prosauropods like ''Massospondylus'' likely had abdominal and cervical air sacs, based on the evidence for them in sister taxa (theropods and sauropods). The study concluded that it was impossible to determine whether prosauropods had a bird-like flow-through lung, but that the air sacs were almost certainly present.<ref name="Wedel">{{cite journal| last =Wedel| first =Mathew| title =What pneumaticity tells us about 'prosauropods', and vice versa| journal =Special Papers in Palaeontology| volume =77| issue =| pages =207–222| publisher =| location =| year =2007| url =http://sauroposeidon.net/Wedel_2007_pneumaticity-and-prosauropods.pdf |format=PDF| accessdate =2007-10-31}}</ref>

==References==
{{Reflist|2}}

==Further reading==
{{refbegin}}
* Chinsamy, A. (1992). "Ontogenetic growth of the dinosaurs ''Massospondylus carinatus'' and ''Syntarsus rhodesiensis''". In: ''Abstracts of papers. Society of Vertebrate Paleontology, fifty-second annual meeting''. Royal Ontario Museum Toronto, Ontario, ''Journal of Vertebrate Paleontology'', 12, 3, 23A.
* Gow, C. E. (1990). "Morphology and growth of the ''Massospondylus'' braincase (Dinosauria, Prosauropoda)". ''Palaeontologia Africana'', 27, 59–75.
* Hinic, S. (2002). "The cranial anatomy of ''Massospondylus carinatus'' Owen, 1854 and its implications for prosauropod phylogeny". ''Journal of Vertebrate Paleontology''. Abstracts of papers. Society of Vertebrate Paleontology, 22, Supplement to number 3, 65A.
* Martínez, R. (1999). "The first South American record of ''Massospondylus'' (Dinosauria: Sauropodomorpha)". ''Journal of Vertebrate Paleontology'', Abstracts of papers. Society of Vertebrate Paleontology, 20–23 October, 19, Suppl. 3, 61A.
* Martínez, R.N. (1999). "''Massospondylus'' (Dinosauria: Sauropodomorpha) in northwestern Argentina". ''Abstracts VII International Symposium on Mesozoic Terrestrial Ecosystems, Buenos Aires'', 40.
{{refend}}

==External links==
{{portalpar|Dinosaurs}}
{{Commons|Massospondylus}}
{{Wikispecies|Massospondylus}}
{{Wiktionary|Massospondylus}}
*[http://brodel.med.utoronto.ca/~heidir/interface.html Locomotion and Ontogeny of ''Massospondylus carinatus''] from the University of Toronto at Missisauga.
*[http://www.palaeos.com/Vertebrates/Units/330Sauropodomorpha/330.100.html#Massospondylidae Massospondylidae] from Palaeos.com (technical).
*[http://www.dinodata.org/index.php?option=com_content&task=view&id=4912&Itemid=110 ''Massospondylus''] at DinoData.org.
*[http://www.primeorigins.co.za/young_minds/massospondylus.htm ''Massospondylus''] from PrimeOrigins.co.za (for children).
*[http://www.wits.ac.za/geosciences/bpi/embryos.htm "Oldest known dinosaur embryos identified"] University of the Witwatersrand.
*{{waybackdate |site=http://news.nationalgeographic.com/news/2005/07/0728_050728_dinoembryo.html |title="Rare fossil embryos reveal growth"|date=20070503162825}} ''National Geographic''.
*[http://www.users.qwest.net/~jstweet1/sauropodomorpha.htm Sauropodomorpha] on ''Thescelosaurus!''

{{featured article}}

[[Category:Dinosaurs of Africa]]
[[Category:Jurassic dinosaurs]]
[[Category:Prosauropods]]

[[ast:Massospondylus]]
[[map-bms:Massospondylus]]
[[br:Massospondylus]]
[[ca:Massospondylus]]
[[cs:Massospondylus]]
[[cy:Massospondylus]]
[[da:Massospondylus]]
[[de:Massospondylus]]
[[es:Massospondylus]]
[[eo:Massospondylus]]
[[fr:Massospondylus]]
[[gl:Massospondylus]]
[[id:Massospondylus]]
[[it:Massospondylus carinatus]]
[[sw:Massospondylus]]
[[la:Massospondylus]]
[[lv:Massospondylus]]
[[lb:Massospondylus]]
[[hu:Massospondylus]]
[[nl:Massospondylus]]
[[no:Massospondylus]]
[[nn:Massospondylus]]
[[pl:Masospondyl]]
[[pt:Massospondylus]]
[[ro:Massospondylus]]
[[simple:Massospondylus]]
[[sk:Massospondylus]]
[[sl:Massospondylus]]
[[fi:Massospondylus]]
[[sv:Massospondylus]]
[[vo:Massospondylus]]
[[zh:大椎龍]]

Revision as of 07:38, 11 October 2008

Kjell Johansson is the name of:

Retrieved from "https://en.wikipedia.org/w/index.php?title=Massospondylus&oldid=244529791"