Maotianshan shales 101918 224796519 2008-07-10T13:25:55Z Totnesmartin 1785980 /* External links */ oops {{Listtable|date=January 2008}}[[Image:Maotianshania-cylindrica.jpg|thumb|right|''Maotianshania cylindrica'', a [[fossil]] [[Nematomorpha|nematomorph worm]], Early [[Cambrian]], Chengjiang Maotianshan Shales]] In the '''Maotianshan shales''' is a lower [[Cambrian]] ''[[Lagerstätte|Konservat Lagerstätte]]'' named for Maotianshan Hill ({{zh-stp|t={{linktext|帽|天|山}}|s={{linktext|帽|天|山}}|p=Màotiānshān}}) in [[Chengjiang]] County, [[Yunnan]] Province, [[China]]. More commonly, the extremely diverse assemblage of organisms are referred to as the '''Chengjiang biota''' for the multiple scattered [[fossil]] sites in Chengjiang. The Chengjiang fauna occur in outcrops of the Qiongzhusi Formation that date to between 525 and {{Ma|520}} - a period situated in the middle of the early [[Cambrian]] epoch and at least some 10 million years older than the [[Burgess Shale]]. The Maotianshan shale is one of some forty Cambrian fossil locations worldwide exhibiting exquisite preservation of rarely preserved, non-mineralized soft tissue, comparable to the fossils of the Burgess Shale. ==History and scientific significance== Although fossils from the region have been known from the early part of the twentieth century, Chengjiang was first recognized for its exquisite states of preservation with the 1984 discovery of the [[naraoiidae|naraoiid]] ''[[Misszhouia]]'', a soft-bodied relative of [[trilobite]]s. Since then, the locality has been intensively studied by scientists from throughout the world, yielding a constant flow of new discoveries and an extensive literature expressing scientific debate surrounding the interpretation of discoveries. Over this time, various taxa have been revised or re-assigned to different groups. Interpretations have led to many refinements of the [[phylogeny]] of various groups and even the erection of the new phylum [[Vetulicolia]] of primitive [[deuterostomes]]. The Chengjiang biota already has all the animal groups found in the Burgess Shale; however, since it is ten million years older, it more strongly supports the deduction that metazoans diversified earlier or faster in the early Cambrian than does the Burgess Shale fauna alone. The preservation of an extremely diverse faunal assemblage renders the Maotianshan shale the world’s most important locality for understanding the evolution of early multi-cellular life, and particularly the members of phylum [[Chordata]], which includes all [[vertebrates]]. The Chengjiang fossils comprise the oldest diverse [[metazoan]] assemblage above the [[Proterozoic]]-[[Phanerozoic]] transition, and thus the [[fossil record]]’s best data source for understanding the apparently rapid diversification of life known as the [[Cambrian Explosion]]. ==Preservation and Taphonomy== Fossils occur in a section of mudstone fifty meters thick in the Yuanshan Member of the Qiongzhusi Formation. The Yuanshan Member is extensive, covering tens of thousands of square kilometers of eastern Yunnan Province, where there are numerous, scattered outcrops yielding fossils. Studies of the strata are consistent with a tropical environment with sea level changes and tectonic activity. The region is believed to have been a shallow sea with a muddy bottom. The preserved fauna is primarily [[benthic]] and was likely buried by periodic [[turbidity current]]s, since most fossils do not show evidence of post mortem transport. Like the younger Burgess Shale fossils, the paleo-environment enabled preservation of non-mineralized, soft body parts. Fossils are found in thin layers less than an inch thick. The soft parts are preserved as aluminosilicate films, often with high oxidized iron content, and often exhibiting exquisite details. ==Fauna== The Chengjiang biota comprises an extremely diverse faunal assembly, with some 185 species described in the literature [[as of June 2006]]. Of these, nearly half are arthropods, few of which had the hard, mineral-reinforced exoskeletons characteristic of all later arthropoda; only about 3% of the organisms known from Chengjiang have hard shells, and most of those are the [[trilobite]]s, of which there are five species, all of which have been found with traces of legs, antennae, and other soft body parts, an exceedingly rare occurrence in the fossil record. Phylum [[Porifera]] (sponges; 15 species) and [[Priapulida]] (16 species) are also well represented. Other phyla represented are [[Brachiopoda]], [[Chaetognatha]], [[Cnidaria]], [[Ctenophora]], [[Echinodermata]], [[Hyolitha]], [[Nematomorpha]], [[Phoronida]], [[Protista]], and [[Chordata]]. About one in eight animals are [[Problemata|problematic forms]] of uncertain affinity, some of which may have been evolutionary experiments that survived for only a brief period as benthic environments rapidly changed in the Cambrian. Chengjiang is the richest source of the [[lobopodia]], often considered a distinct phylum, with six genera represented: ''[[Luolishania]]'', ''[[Paucipodia]]'', ''[[Cardiodictyon]]'','' [[Hallucigenia]]'' (also known from the Burgess Shale), ''[[Microdictyon]]'', and ''[[Onychodictyon]]''. Perhaps the most important fossils from Chengjiang are eight possible members of phylum [[Chordata]], the phylum to which all vertebrates belong. The most famous is ''[[Myllokunmingia]]'', possibly a very primitive agnathid (i.e., [[jawless fish]]). Similar to ''Myllokunmingia'' is ''[[Haikouichthys]] ercaicunensis'', another primitive fish-like animal. The enigmatic ''[[Yunnanozoon|Yunnanozoon lividum]]'' is considered to be the earliest [[hemichordate]], possessing many of the characteristic chordate features and providing an anatomical link between [[invertebrates]] and chordates. ''[[Haikouella lanceolata]]'' is described to be the earliest [[craniate]]-like chordate. This fish-like animal has many similarities to ''Y. lividum'', but also differs in several aspects: it has a discernible heart, dorsal and ventral aorta, gill filaments, and a [[notochord]] (neural chord). At present, there is no agreement as to the systematic placement of the [[Vetulicola]], represented by seven species from Chengjiang: originally described as crustacean arthropods, the Vetulicola were later erected as a new phylum of primitive [[deuterostome]]s by D.G. Shu et al. (Shu 2001). Another researcher places them with the urochordates, based on putative affinity with the Phylum Chordata. They are thought to have been swimmers that either were filter feeders or detritivores. Some two dozen animals from the Chengjiang biota are problematic regarding phylogenetic assignment. Among these, ''[[Anomalocaris]] saron'', the alleged predatory terror of the early Cambrian, is the most famous. Shu (2006) recently described ''[[Stromatoveris]] psygmoglena'' as a possible [[Bilateria|bilateran]] missing link between [[Ediacaran]] fronds and Cambrian [[ctenophores]]. ==List of Chengjiang Biota species by phylum== <div style="-moz-column-count:3; column-count:3;"> ===[[Animal|Kingdom Animalia]]=== '''[[Arthropoda|Phylum Arthropoda]]''' - 77 species *''[[Acanthomeridion]] serratum'' *''[[Alalcomenaeus]]'' *''[[Almenia]] spinosa'' *''[[Anomalocaris]] saron'' *''[[Anomalocaris]] symbrachiata'' *''[[Apiocephalus]] elegans'' *''[[Branchiocaris]] yunnanensis'' *''[[Canadaspis]] laevigata'' *''[[Chengjiangocaris]] longiformis'' *''[[Chuandianella]] ovata'' *''[[Cindarella]] eucalla'' *''[[Clypecaris]] pteroidea'' *''[[Combinivalvula]] chengjiangensis'' *''[[Comptaluta]] inflata'' *''Comptulata leshanensis'' *''[[Cyathocepalus]] bispinosus'' *''[[Dianchia]] mirabilis'' *''[[Diplopyge]] forcipatus'' *''Diplopyge minutus'' *''[[Dongshanocaris]] foliiformis'' *''[[Ercaia]] minuscula'' *''[[Ercaicunia]] multinodosa'' *''[[Forfexicaris valida]]'' *''[[Forticeps foliosa]]'' *''[[Fuxianhuia]] protensa'' *''[[Glossocaris]] occulatus'' *''[[Haikoucaris]] ercaiensis'' *''[[Isoxys]] auritus'' *''Isoxys curvirostratus'' *''Isoxys paradoxus'' *''[[Jianfengia]] multisegmentalis'' *''[[Jianshania]] furcatus'' *''[[Jiucunella]] paulula'' *''[[Kuamaia]] lata'' *''Kuamaia muricata'' *''[[Kuanyangia]] pustulosa'' *''[[Kunmingella]] angustacostata'' *''Kunmingella douvillei'' *''Kunmingella guanshanensis'' *''[[Kunmingocaris]] bispinosus'' *''[[Kunyangella]] cheni'' *''[[Leanchoilia]] asiatica'' *''Leanchoilia illecebrosa'' *''[[Liangshanella]] liangshenensis'' *''[[Mafangia]] subscalaria'' *''Mafangocaris multinodus'' *''[[Malongella]] bituerculata'' *''[[Occacaris oviformis]]'' *''[[Odaraia]] eurypetala'' *''[[Ovalicephalis]] mirabilis'' *''[[Panlongia]] spinosa'' *''Panlongia tetranudosa'' *''[[Parakunmingella]] malongensis'' *''[[Parapaleomerus]] sinensis'' *''[[Pectocaris]] spatiosa'' *''[[Petalilium]] latus'' *''[[Pisinnocaris]] subconigera'' *''[[Primicaris]] larvaformis'' *''[[Pseudoiulia]] cambriensis'' *''[[Pterotum]] triacanthus'' *''[[Pygmaclypeatus]] daiensis'' *''[[Rectifacies]] abnormalis'' *''[[Rhombicalvaria]] acanthi'' *''[[Saperion]] glumaceum'' *''[[Sidneyia]] sinica'' *''[[Sinoburius]] lunaris'' *''[[Skioldia]] aldna'' *''[[Spinokunmingella]] typical'' *''[[Sunella]] grandis'' *''[[Squamacula]] clypeata'' *''[[Syrrhaptis]] intestinalis'' *''[[Urokodia]] aequalis'' *''[[Tanglangia]] caudata'' *''[[Trigoides]] aclis'' *''[[Tsunydiscus]] aclis'' *''[[Tsunyiella]] daindongensis'' *''[[Tuzoia]] sinensis'' - a Phyllocarid *''[[Waptia]] ovata'' *''[[Wutingella]] binodosa'' *''[[Xandarella]] spectaculum'' *''[[Yiliangocaris]] ellipticus'' *''[[Yunnanocaris]] megista'' '''Phylum Arthropoda - [[Arachnomorpha]] - 2 species''' *''[[Misszhouia]] longicaudata'' *''[[Naraoia]] spinosa'' '''Phylum Arthropoda - Class [[Trilobite|Trilobita]] - 5 species''' *''[[Eoredlichia]] intermedia''; Family Redlichiidae *''[[Kuanyangia]] pustulosa''; Family Redlichiidae *''[[Wutingaspis]] tingi''; Family Redlichiidae *''[[Yunnanocephalus]] yunnanensis''; Family Yunnanocephalidae *''[[Palaeolenus]] lantenoisi''; Family Palaeolenidae '''Phylum [[Brachiopod]]a - 5 species''' *''[[Diandongia]] pista'' *''[[Heliomedusa]] orienta'' *''[[Lingulella]] chengjiangensis'' *''[[Lingulellotreta]] malongensis'' *''[[Longtancunella]] chengjiangensis'' '''Phylum [[Chaetognatha]] - 1 species''' *''[[Eognathacantha]] ercainella'' '''Phylum [[Cnidaria]] - 2 species''' *''[[Priscapennamarina]] angusta'' *''[[Xianguangia]] sinica'' '''Phylum [[Chordate|Chordata]]''' - 8 species *''[[Cathaymyrus]] diadexus'' *''Cathaymyrus haikouensis'' *''[[Haikouella]] jianshanensis'' *''[[Haikouella]] lanceolata'' *''[[Haikouichthys]] ercaicunensis'' *''[[Myllokunmingia]] fengjiaoa'' *''[[Shancouclava]] anningense'' - a [[Tunicate]] *''[[Zhongxiniscus]] intermedius'' '''Phylum [[Ctenophore|Ctenophora]]''' - 3 species *''[[Maotianoascus]] octonarius'' *''[[Sinoascus]] paillatus'' *''[[Stromatoveris]] psygmoglena'' '''Phylum [[Echinoderm]]ata''' - 1 species *''[[Cotyledion]] tylodes'' '''Phylum [[Hyolitha]]''' - 8 species *''[[Ambrolinevitus]] maximus'' *''Ambrolinevitus platypluteus'' *''Ambrolinevitus ventricosus'' *''[[Burithes]] yunnanensis'' *''[[Glossolithes]] magnus'' *''[[Linevitus]] billingsi'' *''Linevitus flabellaris'' *''Linevitus opimus'' '''Phylum [[Lobopodia]]''' - 6 species *''[[Cardiodictyon]] catenulum'' *''[[Hallucigenia|Hallucigenia fortis]]'' *''[[Luolishania]] longicruris'' *''[[Microdictyon]] sinicum'' *''[[Onychodictyon]] ferox'' *''[[Paucipodia]] inermis'' '''Phylum [[Nematomorpha]]''' - 3 species *''[[Cricocosmia]] jinningensis'' *''[[Maotianshania]] cylindrica'' *''[[Palaeoscolex]] sinensis'' '''Phylum [[Phoronida]]''' - 1 species *''[[Iotuba]] chengjiangensis'' '''Phylum [[sea sponge|Porifera]]''' - 15 species *''[[Allantospongia]] mica'' *''[[Choia]] xiaolantianensis'' *''[[Choiaella]] radiata'' *''[[Hazelia]]'' sp. *''[[Leptomitella]] confusa'' *''Leptomitella conica'' *''Leptomitella metta'' *''[[Leptomitus]] teretiusculus'' *''[[Paraleptomitella]] dictyodroma'' *''Paraleptomitella globula'' *''[[Quadrolaminiella]] crassa'' *''Quadrolaminiella diagonalis'' *''[[Saetaspongia]] densa'' *''[[Sinfoflabrum]] antiquum'' *''[[Triticispongia]] diagonata'' '''Phylum [[Priapulida]]''' - 16 species *''[[Acosmia]] maotiania'' *''[[Archotuba]] conoidalis'' *''[[Corynetis]] brevis'' *''[[Gantoucunia]] aspera'' *''[[Lagenula]] triolata'' *''[[Oligonodus]] specialis'' *''[[Paraselkirkia]] jinningensis'' *''[[Palaeopriapulites]] parvus'' *''[[Protopriapulites]] haikouensis'' *''[[Sandaokania]] latinodosa'' *''[[Selkirkia]] elongata'' *''Selkirkia sinica'' *''[[Sicyophorus]] rarus'' *''[[Xiaoheiqingella]] peculiaris'' *''[[Xishania]] longgiusula'' *''[[Yunnanopriapulus]] halteroformis'' '''[[Vetulicolia|Phylum Vetulicolia]]''' - 7 species *''[[Banffia]] confusa'' *''[[Didazoon]] hoae'' *''[[Vetulicola]] cuneata'' *''Vetulicola gantoucunensis'' *''Vetulicola rectangulata'' *''[[Xidazoon]] stephanus'' *''[[Yunnanozoon]] lividum'' (disputed, see Enigmatic below) '''Phylum Uncertain''' - 4 species *''[[Amplectobelua]] symbrachiata'' *''[[Anomalocaris|Anomalocaris saron]]'' *''[[Cucumericrus]] decoratus'' *''[[Parapeytoia]] yunnanensis '' '''Enigmatic''' - 24 species *''[[Allonnia]] phrixothrix'' *''[[Amiskwia]] sinica'' *''[[Anthrotum]] robustus'' *''[[Batofasciculus]] ramificans'' *''[[Cambrotentacus]] sanwuia'' *''[[Conicula]] straita'' *''[[Dinomischus]] venustus'' *''[[Discoides]] abnormalis'' *''[[Eldonia]] eumorpha'' *''[[Facivermis]] yunnanicus'' *''[[Hippotrum]] spinatus'' *''[[Jiucunia]] petalina'' *''[[Maanshania]] crusticeps'' *''[[Macrocephalus]] elongates'' *''[[Parvulonoda]] dubia'' *''[[Phacatrum]] tubifer'' *''[[Phasangula]] striata'' *''[[Phlogites]] brevis'' *''Phlogites longus'' *''[[Priscapennamarina]] angusta'' *''[[Pristitoites]] bifarius'' *''[[Rhipitrus]] calvifer'' *''[[Rotadiscus]] grandis'' *''[[Yunnanozoon|Yunnanozoon lividum]]'' - earliest known [[hemichordate]] ===Kingdom [[Protist]]a (algae)=== *''[[Fuxianospira]] gyrata'' *''[[Megaspirellus]] houi'' *''[[Sinocylindra]] yunnanensis'' *''[[Yuknessia]]'' sp. </div> ==References== *Conway-Morris, S. (2003). The Cambrian "explosion" of metazoans and molecular biology: would Darwin be satisfied? Int J Dev Biol, 47(7-8), 505-515. *[http://www.fossilmuseum.net/Fossil_Sites/Chengjiang.htm Fossils of the Chengjiang Maotianshan Shale] - URL retrieved [[September 20]], [[2006]] *Hou, Xian-Guang; Aldridge, Richard J., Bengstrom, Jan; Siveter, David J. ;Feng, Xiang-Hong 2004; The Cambrian Fossils of Chengjang, China, Blackwell Science Ltd, 233 pp. *[http://palaeo.gly.bris.ac.uk/Palaeofiles/Lagerstatten/chngjang/ Preservation, Taphonomy and Palaeoecology of the Chengjiang Biota] - URL retrieved Septermber 20 2006 *Shu, D-G; Luo, H-L; Conway Morris, S.; Zhang X-L; Hu, S-X; Chen, L. ;Han, J.; Zhu, M.;Li, Y; Chen, L-Z 1999, Lower Cambrian Vertebrates from South China, Nature 402 pp 42-46. *Shu, D. G., Morris, S. C., Han, J., Chen, L., Zhang, X. L., Zhang, Z. F., et al. (2001). Primitive deuterostomes from the Chengjiang Lagerstatte (Lower Cambrian, China). Nature, 414(6862), 419-424. *Shu, D., Morris, S. C., Zhang, Z. F., Liu, J. N., Han, J., Chen, L., et al. (2003). A new species of yunnanozoan with implications for deuterostome evolution. Science, 299(5611), 1380-1384. *Shu, D. G., Morris, S. C., Han, J., Zhang, Z. F., & Liu, J. N. (2004). Ancestral echinoderms from the Chengjiang deposits of China. Nature, 430(6998), 422-428. *Shu, D. G., Morris, S. C., Han, J., Li, Y., Zhang, X. L., Hua, H., et al. (2006). Lower Cambrian vendobionts from China and early diploblast evolution. Science, 312(5774), 731-734. *Waloszek, D., & Maas, A. (2005). The evolutionary history of crustacean segmentation: a fossil-based perspective. Evol Dev, 7(6), 515-527. *Xian-guang, H., Aldridge, R. J., Siveter, D. J., & Xiang-hong, F. (2002). New evidence on the anatomy and phylogeny of the earliest vertebrates. Proc Biol Sci, 269(1503), 1865-1869. *Zhang, X.; Han J.; Zhang Z.; Liu H.; and Shu D. (2003) Reconsideration of the supposed naraoiid larva from the Early Cambrian Chngjiang Lagerstätte, South China. Palaeontology 46(3):447-66. *Zhang, X. G., & Hou, X. G. (2004). Evidence for a single median fin-fold and tail in the Lower Cambrian vertebrate, Haikouichthys ercaicunensis. J Evol Biol, 17(5), 1162-1166. == See also == * [[Geography of China]] * [[Stephen Jay Gould]], ''[[Wonderful Life (book)|Wonderful Life]]'' ==External links== * {{cite web | url= http://www.uni-wuerzburg.de/palaeontologie/Stuff/casu30.htm | title=Chengjiang | format=Web page | accessmonthday=November 22 | accessyear=2005 }} * http://www.fossilmuseum.net/Fossil_Sites/Chengjiang/Chengjiang-Biota.htm [[Category:Cambrian]] [[Category:Paleontological sites]] [[Category:Yunnan]] [[Category:Geologic formations]] [[Category:Maotianshan shales fossils| ]] [[ca:Esquists de Maotianshan]] [[de:Maotianshan-Schiefer]] [[es:Esquistos de Maotianshan]] [[fr:Schistes de Maotianshan]] [[nl:Maotianshan shales]] [[ja:澄江動物群]] [[zh:澄江动物群]]