Vertebrate 36856 223624874 2008-07-04T23:14:04Z Iridescent 937705 Reverted edits by [[Special:Contributions/68.231.85.216|68.231.85.216]] to last version by Useight (using [[WP:HG|Huggle]]) {{Taxobox | name = Vertebrates | fossil_range = [[Early Cambrian]] - Recent | image = Blue-toungued skink444.jpg | image_width = 250px | image_caption = [[Blotched Blue-tongued Lizard]], ''Tiliqua nigrolutea'' | regnum = [[Animal]]ia | phylum = [[Chordata]] {{Taxobox norank entry | taxon = [[Craniata]]}} | subphylum = '''Vertebrata''' | subphylum_authority = [[Georges Cuvier|Cuvier]], 1812 | subdivision_ranks = Classes and Clades | subdivision = See below }} '''Vertebrates''' are members of the [[subphylum]] '''Vertebrata''', [[chordates]] with [[Vertebra|backbone]]s or [[Vertebral column|spinal column]]s. The grouping sometimes includes the [[hagfish]], which have no vertebrae, but are genetically quite closely related to [[lamprey]]s, which do have vertebrae.<ref name=hagfish/> For this reason, the sub-phylum is sometimes referred to as "Craniata", as all members do possess a [[cranium]]. About 58,000 [[species]] of vertebrates have been described.<ref>{{cite web |url=http://www.iucn.org/bookstore/HTML-books/Red%20List%202004/completed/table2.1.html | title=A Global Species Assessment | publisher=World Conservation Union |author=Jonathan E.M. Baillie, et al. |year=2004}}</ref> Vertebrata is the largest subphylum of chordates, and contains many familiar groups of large land animals. Vertebrates comprise [[cyclostome]]s, [[bony fish]], [[sharks]] and [[rays]], [[amphibian]]s, [[reptiles]], [[mammals]], and [[birds]]. Extant vertebrates range in size from the [[carp]] species ''[[Paedocypris]]'', at as little as 7.9 mm (0.3 inch), to the [[Blue Whale]], at up to 33 m (110 ft). ==Anatomy and morphology== One characteristic of the subphylum are that all members have muscular systems that mostly consist of paired masses, as well as a [[central nervous system]] which is partly located inside the backbone (if one is present). The defining characteristic of a vertebrate is considered the [[backbone]] or [[spinal cord]], a [[brain]] case, and an internal skeleton, but the latter do not hold true for [[lampreys]], and the former is arguably present in some other [[chordate]]s. Rather, ''all'' vertebrates are most easily distinguished from ''all'' other chordates by having a clearly identifiable head, that is, [[sensory organs]] - especially [[eye]]s are concentrated at the fore end of the body and there is pronounced [[cephalization]]. Compare the [[lancelet]]s which have a mouth but not a well-developed head, and have light-sensitive areas along their entire back.<ref>{{cite web |url=http://webs.lander.edu/rsfox/invertebrates/branchiostoma.html |title=Branchiostoma |author=Richard Fox | year=2004}}</ref> ==Evolutionary history== Vertebrates originated about 500 million years ago during the [[Cambrian explosion]], which is part of the [[Cambrian]] period. The earliest known vertebrate is [[Myllokunmingia]].<ref> {{cite journal|title=Lower Cambrian vertebrates from south China | author=Shu et al. |date=[[November 4]] [[1999]]|journal=Nature| volume=402|pages=42–46|doi= 10.1038/46965}}</ref> According to recent molecular analysis [[Hagfish|Myxini]] (hagfish) also belong to Vertebrates. Others consider them a sister group of Vertebrates in the common taxon of [[Craniata]].<ref name=hagfish>{{cite journal|title=Monophyly of Lampreys and Hagfishes Supported by Nuclear DNA–Coded Genes | author=Kuraku et al. |date=December 1445 B.C.|journal=Journal of Molecular Evolution {{doi|10.1007/PL00006595}} | volume = 49 | pages = 729|doi=10.1007/PL00006595}} | volume = 49 | pages = 729}}</ref> ==Fossil record== The earliest known fossil records of vertebrates are ''[[Myllokunmingia fengjiaoa]]'' and ''[[Haikouichthys ercaicunensis]]'', dating somewhere between 513-542 [[mya (unit)|mya]] during the [[Early Cambrian]]. The fossils were discovered in [[Yunnan]], [[People's Republic of China|China]][http://paleodb.org/cgi-bin/bridge.pl]. == Taxonomy and classification== Classification after Janvier (1981, 1997), Shu ''et al''. (2003), and Benton (2004).<ref name="Benton2004">{{cite book | last =Benton | first =Michael J. | authorlink =Michael Benton | title =Vertebrate Palaeontology | publisher =[[Blackwell Publishing]] | date= 2004-11-01 |edition=Third Edition | location = | pages =455 pp. | url =http://palaeo.gly.bris.ac.uk/benton/vertclass.html | doi = | id = | isbn =0632056371/978-0632056378}}</ref> * '''Subphylum Vertebrata''' ** (Unranked group) [[Hyperoartia]] ([[lamprey]]s) ** Class †[[Conodonta]] ** Subclass †[[Pteraspidomorphi]] ** Class †[[Thelodonti]] ** Class †[[Anaspida]] ** Class †[[Galeaspida]] ** Class †[[Pituriaspida]] ** Class †[[Osteostraci]] ** '''Infraphylum [[Gnathostomata]]''' (jawed vertebrates) :::* Class †[[Placodermi]] (Paleozoic armoured forms) :::* Class [[Chondrichthyes]] (cartilaginous fish) :::* Class †[[Acanthodii]] (Paleozoic "spiny sharks") ::* Superclass [[Osteichthyes]] (bony fish) :::* Class [[Actinopterygii]] (ray-finned fish) :::* Class [[Sarcopterygii]] (lobe-finned fish) ::::* Subclass [[Coelacanthimorpha]] ([[coelacanth]]s) ::::* Subclass [[Dipnoi]] (lungfish) ::::* Subclass [[Tetrapodomorpha]] (ancestral to tetrapods) ::* Superclass [[Tetrapod]]a (four-limbed vertebrates) ::::* Class [[amphibian|Amphibia]] (amphibians) :::* Series [[Amniota]] (amniotic embryo) ::::* Class [[Sauropsida]] (reptiles and birds) :::::* Class [[bird|Aves]] (birds) ::::* Class [[Synapsida]] (mammal-like reptiles) :::::* Class [[Mammal]]ia (mammals) ==Etymology== The word ''vertebrate'' derives from Latin ''vertebrātus'' ([[Pliny]]), meaning ''having joints''. It is closely related to the word ''[[vertebra]]'', which refers to any of the bones or segments of the spinal column.<ref>{{cite web | title=vertebra |publisher=Dictionary.com. |work=Online Etymology Dictionary |author=Douglas Harper, Historian |url=http://dictionary.reference.com/browse/vertebra}}</ref> ==References== {{reflist}} ==Bibliography== <div class="references-small"> * {{cite book | last =Kardong | first =Kenneth V. | authorlink =Kenneth Kardong | title =Vertebrates: Comparative Anatomy, Function, Evolution | edition = second edition | publisher =[[McGraw-Hill]] | date= 1998 | location =USA | pages =747 pp. | url =http://www.amazon.com/Vertebrates-Comparative-Anatomy-Function-Evolution/dp/0072909560 | doi = | id = | isbn =0-07-115356-X/0-697-28654-1 }} * {{ITIS | ID = 331030| taxon = Vertebrata | year = 2007 | date= 6 August}} </div> == See also == * [[Invertebrate]] * [[Marine vertebrates]] == External links == {{Wikispecies|Vertebrata}} * [http://tolweb.org/Vertebrata/14829 Tree of Life] * [http://www.nature.com/nature/journal/v439/n7079/abs/nature04336.html Tunicates and not cephalochordates are the closest living relatives of vertebrates] {{Chordata}} [[Category:Vertebrates| ]] <!-- interwiki --> [[ang:Hweorfdēor]] [[ar:فقاريات]] [[zh-min-nan:Chek-chui tōng-bu̍t]] [[bs:Kičmenjaci]] [[br:Vertebrata]] [[bg:Гръбначни]] [[ca:Vertebrat]] [[cs:Obratlovci]] [[cy:Fertebrat]] [[da:Hvirveldyr]] [[de:Wirbeltiere]] [[et:Selgroogsed]] [[el:Σπονδυλωτό]] [[es:Vertebrata]] [[eo:Vertebruloj]] [[eu:Ornodun]] [[fa:مهره‌داران]] [[fr:Vertébrés]] [[fy:Wringedier]] [[ga:Veirteabrach]] [[gl:Vertebrata]] [[ko:척추동물]] [[hr:Kralježnjaci]] [[id:Vertebrata]] [[ia:Vertebrato]] [[is:Hryggdýr]] [[it:Vertebrata]] [[he:בעלי חוליות]] [[jv:Vertebrata]] [[ka:ხერხემლიანები]] [[ku:Movikdar]] [[la:Vertebrata]] [[lv:Mugurkaulnieki]] [[lt:Stuburiniai]] [[li:Gewervelde diere]] [[ln:Nyama ya mikúwa]] [[hu:Gerincesek]] [[mk:‘Рбетници]] [[mr:पृष्ठवंशी प्राणी]] [[ms:Vertebrat]] [[nl:Gewervelden]] [[ja:脊椎動物]] [[no:Virveldyr]] [[nn:Virveldyr]] [[oc:Vertebrata]] [[pl:Kręgowce]] [[pt:Vertebrados]] [[ro:Vertebrata]] [[qu:Tulluyuq]] [[ru:Позвоночные]] [[scn:Vertebrata]] [[simple:Vertebrate]] [[sk:Stavovce]] [[sl:Vretenčarji]] [[szl:Kryngowce]] [[sr:Кичмењаци]] [[su:Vertebrata]] [[fi:Selkärankaiset]] [[sv:Ryggradsdjur]] [[tl:Vertebrata]] [[ta:முதுகெலும்பிகள்]] [[te:సకశేరుకాలు]] [[th:สัตว์มีกระดูกสันหลัง]] [[vi:Động vật có xương sống]] [[tr:Omurgalılar]] [[uk:Хребетні]] [[wa:Cronzoxhî]] [[yi:ווערטייברעיטס]] [[bat-smg:Stoborėnē]] [[zh:脊椎动物]]