Utente:Marrabbio2/Pesci: differenze tra le versioni
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m fix errore Lint - Tag di chiusura mancante using AWB |
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Riga 1:
[[File:Ostracoderm and placoderm.jpg|right|thumb|250px|I primi pesci fossili: [[ostracodermi]] (sopra) e [[Placodermi]]]]
L'evoluzione dei pesci non è studiata come un singolo evento da quanto la riorganizzazione sistematica dei [[pesci]] ha portato al disconocimento di questi come gruppo monofiletico{{sfn|Lecointre|Le Guyader|2007|ps=}}.
I primi pesci apparvero durante la cosidetta [[esplosione cambriana]], circa 530 milioni di anni fa: questi ritrovamenti [[fossili]] appartengono ad un gruppo di piccoli pesci corazzati senza mascelle, noti come [[ostracodermi]], oggi estinti. Un [[clade]] imparentato ed esistente, comprendente le [[Lampreda|lamprede]]. Le prime mascelle appaiono invece nei [[Placodermi]]. La diversità di questi vertebrati indica il vantaggio evolutivo di una [[bocca]] provvista di mascelle, anche se ancora non è chiaro chiaro se il vantaggio comprenda un morso con maggior resistenza, una respirazione migliorata o una combinazione di entrambi i fattori.
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Riga 281 ⟶ 265:
| colspan="3" style="text-align:center; background:#ddf8f8;"| [[Ordoviciano]] (488–443 milioni di anni fa): i pesci, la prima forma di vita vertebrata, continuano ad evolvere: compaiono i primi pesci con mandibole ([[Gnathostomata]]). </br>La vita sulla terraferma non si è ancora differenziata.
|-
| [[File:
| [[Heterostraci]]
| [[Heterostraci]] è una classe estinta di agnati vertebrati che viveva principalmente in ambienti marini e di estuario. Sono apparsi all'inizio dell'Ordoviciano e si estinse alla fine del Devoniano. Differivano dagli altri pesci senza mandibola del periodo nella disposizione e nell'[[istologia]] delle loro [[scaglia|scaglie]].
Riga 297 ⟶ 281:
| [[Thelodonts]] ''(nipple teeth)'' are a class of small, extinct jawless fishes with distinctive scales instead of large plates of armour. There is debate over whether these represent a [[Monophyly|monophyletic grouping]], or disparate stem groups to the major lines of [[Agnatha|jawless]] and [[Gnathostome|jawed fish]].{{r|Turner1982}} Thelodonts are united by their characteristic "thelodont scales". This defining character is not necessarily a result of shared ancestry, as it may have been [[Convergent evolution|evolved independently by different groups]]. Thus the thelodonts are generally thought to represent a polyphyletic group.{{sfn|Sarjeant|Halstead}} If they are monophyletic, there is no firm evidence on what their ancestral state was.{{sfn|Donoghue|2000|p=206}} These scales were easily dispersed after death; their small size and resilience makes them the most common vertebrate fossil of their time.{{sfn|Turner1999|p=42–78}}{{r|Palaeos: Thelodonti}} The fish lived in both freshwater and marine environments, first appearing during the [[Ordovician]], and perishing during the [[Late Devonian extinction|Frasnian–Famennian extinction event]] of the Late [[Devonian]]. They were predominantly deposit-feeding bottom dwellers, although some species may have been pelagic.
|-
| colspan="3" style="line-height:16px; background:#dddddd;"| <small>The Ordovician ended with the [[Ordovician–Silurian extinction event]] (450–440 Ma). Two events occurred that killed off 27% of all families, 57% of all genera and 60% to 70% of all species.{{r|Baez2006}} Together they are ranked by many scientists as the second largest of the five major extinctions in Earth's history in terms of percentage of [[genus|genera]] that went extinct.</small>
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! rowspan=7 style=background:#60C090 | [[Siluriano]]
Riga 322 ⟶ 306:
| ''[[Guiyu oneiros]]'' è il più antico pesce osseo oggi conosciuto. Presenta una combinazione di caratteri tipici degli [[Actinopterygii]] e dei [[Sarcopterygii]], anche se l'analisi scientifica lo pone più vicino a questi ultimi.
|-
|
| ''[[Andreolepis]]''
| Il genere ''[[Andreolepis]]'' include il più antico [[Actinopterygii|attinopterigio]] oggi conosciuto, ''[[Andreolepis hedei]]'', che comparve nel tardo [[Siluriano]], circa 420 milioni di anni fa.<ref>{{cite journal | author = Min Z | year = 1997 | title = The oldest sarcopterygian fish | url = http://www.researchgate.net/publication/225089993_The_oldest_sarcopterygian_fish/file/d912f4fcb0d2e1d901.pdf | format = PDF | journal = Lethaia | volume = 30 | issue = | pages = 293–304 }}</ref><ref>{{cite journal | author = Märss T | year = 2001 | title = ''Andreolepis'' (Actinopterygii) in the upper Silurian of northern Eurasia | url = http://books.google.co.nz/books?id=0D3ucZP97e4C&pg=PA174&dq=%22Andreolepis+%28Actinopterygii%29+in+the+upper+Silurian+of+northern+Eurasia%22&hl=en&sa=X&ei=tF8IUeHwHYH-lAWo_IGwBA&ved=0CC8Q6AEwAA#v=onepage&q=%22Andreolepis%20%28Actinopterygii%29%20in%20the%20upper%20Silurian%20of%20northern%20Eurasia%22&f=false | journal = Proceedings of the Estonian Academy of Sciences | volume = 50 | issue = 3| pages = 174–189 }}</ref>
Riga 352 ⟶ 336:
| colspan="5" |
|-
! rowspan=18 style=background:#CD9C50 | <div align="center">'''[[Devoniano|D<br>e<br>v<br>o<br>n<br>i<br>a<br>n<br>o]]'''</
| rowspan=6 style=background:#FFC060 | <div align="center">[[Devoniano inferiore]]</
| colspan="3" style="text-align:center; background:#ddf8f8;"| [[Devoniano inferiore]] (419–393 Ma):
|-
Riga 376 ⟶ 360:
| ''[[Laccognathus]]'' ''(pitted jaw)'' was a genus of [[amphibious fish|amphibious]] lobe-finned fish that existed 398–360 Ma.<ref name="ngs">{{cite web|url=http://news.nationalgeographic.com/news/2011/09/110912-ancient-fish-arctic-predator-devonian-fossils-animals-science/|title=Ancient Toothy Fish Found in Arctic—Giant Prowled Rivers|author=[[Christine Dell'Amore|Dell'Amore, C.]]|date=September 12, 2011|publisher=[[National Geographic Society|National Geographic]] Daily News|accessdate=September 13, 2011}}</ref> They were characterized by the three large pits (fossae) on the external surface of the lower jaw which may have had sensory functions.<ref name="avril">{{cite web|url=http://articles.philly.com/2011-09-12/news/30145487_1_tiktaalik-roseae-ted-daeschler/2|title=Fish fossil sheds light on 'Euramerica' phase|author=Tom Avril|date=September 12, 2011|publisher=The Inquirer|accessdate=September 15, 2011}}</ref> ''Laccognathus'' grew to {{convert|1|-|2|m|ft|0}} in length. They had very short dorsoventrally flattened heads, less than one-fifth the length of the body.<ref name="vorobyeva">{{cite journal|author=[[Emiliya Ivanovna Vorobyeva|Vorobyeva, E.I.]]|year=2006|title=A new species of ''Laccognathus'' (Porolepiform Crossopterygii) from the Devonian of Latvia |journal=[[Paleontological Journal|Palaeont. J.]]|volume=40|issue=3|pages=312–322|publisher=Physorg.com|doi=10.1134/S0031030106030129}}</ref> The skeleton was structured so large areas of skin were stretched over solid plates of bone. This bone was composed of particularly dense fibers – so dense that exchange of oxygen through the skin was unlikely. Rather, the dense [[ossification]]s served to retain water inside the body as ''Laccognathus'' traveled on land between bodies of water.<ref name = "witzmann">{{cite journal|author=[[Florian Witzman|Witzman, F.]]|journal=[[Paleodiversity]]|volume=31|issue=5|pages=981–996|year=2011|publisher=The Society of Vertebrate Paleontology|title=A New Species of ''Laccognathus'' (Sarcopterygii, Porolepiformes) from the Late Devonian of Ellesmere Island, Nunavut, Canada}}</ref>
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| rowspan=7 style=background:#FFD090 | <div align="center">[[Devoniano medio]]</
| colspan="3" style="text-align:center; background:#ddf8f8;"| [[Devoniano medio]] (397–385 Ma): [[Chondrichthyes|Cartilaginous fishes]], consisting of [[shark]]s, [[Batoidea|rays]] and [[chimaera]]s, appeared about 395 Ma.
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Riga 402 ⟶ 386:
| colspan="3" style="line-height:16px; background:#dddddd;"| <small>[[Late Devonian extinction]]: 375–360 Ma. A prolonged series of extinctions eliminated about 19% of all families, 50% of all genera{{r|Baez2006}} and 70% of all species. This extinction event lasted perhaps as long as 20 Ma, and there is evidence for a series of extinction pulses within this period.</small>
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| rowspan=5 style=background:#FFE0B0 | <div align="center">[[Devoniano superiore]]</
| colspan="3" style="text-align:center; background:#ddf8f8;"| [[Devoniano superiore]] (383–359 Ma):
|-
| [[File:Dunkleosteus
| ''[[Dunkleosteus]]''
| {{ external media
Riga 427 ⟶ 411:
''[[Materpiscis]]'' ''(mother fish)'' is a [[genus]] of [[ptyctodontid]] [[Placodermi|placoderm]] from about 380 Ma. Known from only one specimen, it is unique in having an unborn [[embryo]] present inside, and with remarkable preservation of a mineralised placental feeding structure ([[umbilical cord]]). This makes ''Materpiscis'' the first known vertebrate to show [[vivipary|viviparity]], or giving birth to live young.{{r|Long2008}} The specimen was named ''Materpiscis attenboroughi'' in honour of [[David Attenborough]].{{r|BBC2008}}
|-
|
| [[Rhizodont]]s
| [[Rhizodont]]s were an order of lobe-finned fish which survived to the end of the Carboniferous, 377–310 Ma. They reached huge sizes. The largest known species, ''[[Rhizodus|Rhizodus hibberti]]'' grew up to 7 metres in length, making it the largest freshwater fish known.
Riga 503 ⟶ 487:
! colspan=4 | Transition from lobe-finned fishes to tetrapods
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| [[File:Eusthenopteron model.jpg|140px]]<small>~385 milioni di anni fa</small>
| ''[[Eusthenopteron]]''
| {{ external media
Riga 516 ⟶ 500:
| ''[[Gogonasus]] (snout from Gogo)'' was a lobe-finned fish known from 3-dimensionally preserved 380 million-year-old fossils found in the [[Gogo Formation]]. It was a small fish reaching 30–40 cm (1 ft) in length.<ref>http://dinosaurs.about.com/od/tetrapodsandamphibians/p/gogonasus.htm</ref> Its skeleton shows several tetrapod-like features. They included the structure of its [[middle ear]], and its fins show the precursors of the forearm bones, the [[radius]] and [[ulna]]. Researchers believe it used its forearm-like fins to dart out of the reef to catch prey. ''Gogonasus'' was first described in 1985 by [[John A. Long]]. For almost 100 years ''[[Eusthenopteron]]'' has been the role model for demonstrating stages in the evolution of lobe-finned fishes to tetrapods. ''Gogonasus'' now replaces ''Eusthenopteron'' in being a better preserved representative without any ambiguity in interpreting its anatomy.
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| [[File:Panderichthys BW.jpg|140px]]<br /><small>~385 milioni di anni fa</small>
| ''[[Panderichthys]]''
| Adapted to muddy shallows, and capable of some kind of shallow water or terrestrial body flexion locomotion. Had the ability to prop itself up.<ref>Nature: [http://www.nature.com/nature/journal/v438/n7071/edsumm/e051222-13.html The pelvic fin and girdle of ''Panderichthys'' and the origin of tetrapod locomotion]</ref><br /> They had large tetrapod-like heads, and are thought to be the most crownward stem fish-tetrapod with paired fins.
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| [[File:Tiktaalik BW.jpg|140px]]<br /><small>~375 milioni di anni fa</small>
| ''[[Tiktaalik]]''
| A fish with limb-like fins that could take it onto land.<ref name=Nature>{{cite journal | journal = [[Nature (journal)|Nature]] | volume = 440 | pages = 757–763 | date = 6 April 2006 | doi = 10.1038/nature04639 | title = A Devonian tetrapod-like fish and the evolution of the tetrapod body plan | url = http://www.nature.com/nature/journal/v440/n7085/abs/nature04639.html | author = Edward B. Daeschler, Neil H. Shubin and Farish A. Jenkins, Jr | pmid = 16598249 | issue = 7085}}</ref> It is an example from several lines of ancient sarcopterygian fish developing adaptations to the oxygen-poor shallow-water habitats of its time, which led to the evolution of tetrapods.<ref name="scientificamerican">[[Jennifer A. Clack]], ''Scientific American'', [http://www.scientificamerican.com/article.cfm?id=getting-a-leg-up-on-land ''Getting a Leg Up on Land''] Nov. 21, 2005.</ref> Paleontologists suggest that it is representative of the [[transitional fossil|transition]] between non-tetrapod vertebrates (fish) such as ''[[Panderichthys]]'', known from fossils 380 million years old, and early tetrapods such as ''[[Acanthostega]]'' and ''[[Ichthyostega]]'', known from fossils about 365 million years old. Its mixture of primitive fish and derived tetrapod characteristics led one of its discoverers, [[Neil Shubin]], to characterize ''Tiktaalik'' as a "[[Tetrapodomorpha|fishapod]]".<ref>John Noble Wilford, ''The New York Times'', [http://www.nytimes.com/2006/04/05/science/05cnd-fossil.html?hp&ex=1144296000&en=fe3427d67e965e46&ei=5094&partner=homepage ''Scientists Call Fish Fossil the Missing Link''], Apr. 5, 2006.</ref><ref name="Shubin 2008">{{cite book|last=Shubin|first=Neil|title=Your Inner Fish|publisher=Pantheon|year=2008|isbn=978-0-375-42447-2}}</ref>
|-
| [[File:Acanthostega BW.jpg|140px]]<br /><small>365 milioni di anni fa</small>
| ''[[Acanthostega]]''
| A fish-like early [[Labyrinthodontia|labyrinthodont]] which occupied weed-filled swamps and changed views about the early evolution of tetrapods.{{r|Clack2005}} [[Polydactyly in early tetrapods|It had eight digits]] on each hand (the number of digits on the feet is unclear) linked by webbing, it lacked wrists, and was generally poorly adapted to come onto land.<ref>"[http://www.devoniantimes.org/Order/re-acanthostega.html Acanthostega gunneri]," ''Devonian Times''.</ref> Sunsequent discoveries revealed earlier transitional forms between ''Acanthostega'' and completely fish-like animals.{{r|Daeschler2006}}
|-
| [[File:Ichthyostega BW.jpg|140px]]<br /><small>374–359 milioni di anni fa</small>
| ''[[Ichthyostega]]''
| {{ external media
Riga 538 ⟶ 522:
Until finds of other early tetrapods and closely related fishes in the late 20th century, ''[[Ichthyostega]]'' stood alone as the transitional fossil between fish and tetrapods, combining a fishlike tail and gills with an amphibian skull and limbs. It possessed lungs and limbs with seven digits that helped it navigate through shallow water in weed-filled swamps.
|-
| [[File:Pederpes22small.jpg|140px]]<br /><small>359–345 milioni di anni fa</small>
| ''[[Pederpes]]''
| ''[[Pederpes]]'' is the earliest known fully terrestrial tetrapod. It is included here to complete the transition of lobe-finned fishes to tetrapods, even though ''Pederpes'' is no longer a fish.
Riga 584 ⟶ 568:
| ''[[Acanthodes]]'' are an extinct genus of [[Acanthodii|spiny shark]].<ref>{{cite journal|year=1880|title=Proceedings of the Royal Physical Society of Edinburgh|volume= V.|pages=p115|url=http://books.google.com/?id=69kKAAAAIAAJ&pg=PA115&dq=Acanthodes+extinct|doi=10.1111/|author1=Edinburgh, Royal Physical Society of}}</ref> It had [[gill]]s but no [[teeth]],<ref name="Nicholson">{{cite book|last=Nicholson|first=Henry Alleyne|coauthors=Richard Lydekker|title=A Manual of Palaeontology|year=1889|url=http://books.google.com/?id=MoAXAAAAYAAJ&pg=PA966&dq=Acanthodes+pectoral+fins|page=966}}</ref> and was presumably a [[filter feeder]].<ref name=EoDP/> ''Acanthodes'' had only two skull bones and were covered in cubical scales. Each paired [[pectoral fin|pectoral]] and [[pelvic fin]]s had one spine, as did the single [[anal fin|anal]] and [[dorsal fin]]s, giving it a total of six spines, less than half that of many other spiny sharks.<ref name=EoDP>{{cite book |editor=Palmer, D.|year=1999 |title= The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals|publisher= Marshall Editions|___location=London|pages= 30–31|isbn= 1-84028-152-9}}</ref> Acanthodians share qualities of both bony fish (osteichthyes) and cartilaginous fish (chondrichthyes), and it has been suggested that they may have been stem chondrichthyans and stem gnathostomes.<ref>Article on Acanthodes as ancestor of Man, http://www.sci-news.com/paleontology/article00396.html, accessed 15 June 2012</ref><ref>Journal article on Acanthodes, http://www.nature.com/nature/journal/v486/n7402/full/nature11080.html, accessed 15 June 2012</ref>
|-
| colspan="3" style="line-height:16px; background:#dddddd;"| <small>The Permian ended with the most extensive [[extinction event]] recorded in [[paleontology]]: the [[Permian-Triassic extinction event]]. 90% to 95% of marine species became [[Extinction|extinct]], as well as 70% of all land organisms. It is also the only known mass extinction of insects.<ref>http://geology.about.com/od/extinction/a/aa_permotrias.htm</ref><ref>http://www.kgs.ku.edu/Extension/fossils/massExtinct.html</ref> Recovery from the Permian-Triassic extinction event was protracted; land ecosystems took 30M years to recover,<ref name="SahneyBenton2008RecoveryFromProfoundExtinction">{{cite journal | url=http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2596898/?tool | author=Sahney, S. and Benton, M.J. | year=2008 | title=Recovery from the most profound mass extinction of all time | journal=Proceedings of the Royal Society: Biological | doi=10.1098/rspb.2007.1370 | volume = 275 | pages = 759–65|format=PDF | pmid=18198148 | issue=1636 | pmc=2596898}}</ref> and marine ecosystems took even longer.{{r|Baez2006}}</small>
|-
! rowspan=5 style="background:#228b22" | [[Triassico|<span style="color:white;">Triassico</span>]]
| colspan="3" style="text-align:center; background:#ddf8f8;"| [[Triassico]] (252–201 Ma): The fish fauna of the Triassic was remarkably uniform, reflecting the fact that very few families survived the Permian extinction. A considerable radiation of ''ray-finned fishes]]'' occurred during the Triassic, laying the foundation for many modern fishes.<ref>[http://www.seaworld.org/animal-info/info-books/bony-fish/scientific-classification.htm Bony fishes] ''[[SeaWorld]]''. Retrieved 2 February 2013.</ref> ''See [[:Category:Triassic fish]].''
|-
| [[File:Perleidus.jpg|140px]]
Riga 602 ⟶ 586:
| ''[[Pholidophorus]]'' was an [[extinct]] genus of [[teleost]], around {{convert|40|cm|in}} long, from about 240–140 Ma. Although not closely related to the modern [[herring]], it was somewhat like them. It had a single [[dorsal fin]], a symmetrical tail, and an [[anal fin]] placed towards the rear of the body. It had large eyes and was probably a fast swimming predator, hunting [[plankton]]ic [[crustacean]]s and smaller fish.{{sfn|The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals|1999|p=38–39}} A very early [[teleost]], ''Pholidophoris'' had many primitive characteristics such as [[ganoid scale]]s and a [[Vertebral column|spine]] that was partially composed of [[cartilage]], rather than [[bone]].{{sfn|The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals|1999|p=38–39}}
|-
| colspan="3" style="line-height:16px; background:#dddddd;"| <small>The Triassic ended with the [[Triassic–Jurassic extinction event]]. About 23% of all families, 48% of all genera (20% of marine families and 55% of marine genera) and 70% to 75% of all species went extinct.<ref name="ucr">{{cite web|url=http://math.ucr.edu/home/baez/extinction |title=extinction |publisher=Math.ucr.edu |date= |accessdate=2008-11-09}}</ref> Non-dinosaurian archosaurs continued to dominate aquatic environments, while [[Diapsid#Taxonomy|non-archosaurian diapsids]] continued to dominate marine environments.<ref name="ucr" /></small>
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! rowspan=3 style="background:#3cb371" | [[Giurassico]]
| colspan="3" style="text-align:center; background:#ddf8f8;"| [[Giurassico]] (199–145 milioni di anni fa):
|-
| [[File:Leedsichthys
| ''[[Leedsichthys]]''
| During the [[Jurassic period]], the primary vertebrates living in the seas were [[fish]] and marine [[reptile]]s. The latter include [[ichthyosaur]]s who were at the peak of their diversity, [[plesiosauria|plesiosaurs]], [[pliosaur]]s, and marine [[crocodilia|crocodiles]] of the families [[Teleosauridae]] and [[Metriorhynchidae]].<ref>Motani, R. (2000), Rulers of the Jurassic Seas, Scientific American vol.283, no. 6</ref> Numerous [[turtle]]s could be found in lakes and rivers.<ref name=nws>{{citation
Riga 640 ⟶ 624:
La loro lentissima evoluzione è dovuta ad alcuni fattori fondamentali: un lungo intervallo generazionale, un'ampia tolleranza alle diverse temperature e salinità delle acque, la mancanza di predatori a causa delle loro grosse dimensioni e l'abbondanza di prede nel loro ambiente.
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| [[File:
| ''[[Enchodus]]''
|
Riga 649 ⟶ 633:
Il più grande dei [[teleostei]] conosciuti, questo pesce del Cretacico raggiungeva una lunghezza di 4,5 metri <ref>Rafferty, John P (2010) [http://books.google.co.nz/books?id=kFd-1DApcRYC&pg=PA219&dq=%22Cretaceous+fish%22+OR+%22Cretaceous+fishes%22&hl=en&sa=X&ei=HkrtUNPWHonKlAWshYGQBQ&ved=0CKEBEOgBMBM#v=onepage&q=%22Cretaceous%20fish%22%20OR%20%22Cretaceous%20fishes%22&f=false ''The Mesozoic Era: Age of Dinosaurs''] pag. 219, Rosen Publishing Group. ISBN 9781615301935.</ref>.
|-
| colspan="3" style="line-height:16px; background:#dddddd;"| <small>The end of the Cretaceous was marked by the [[Cretaceous–Paleogene extinction event]] (K-Pg extinction). There are substantial fossil records of [[Gnathostomata|jawed]] [[fish]]es across the K–T boundary, which provides good evidence of extinction patterns of these classes of marine vertebrates. Within [[Chondrichthyes|cartilaginous fish]], approximately 80% of the [[shark]]s, [[Rajiformes|rays]], and [[skate]]s families survived the extinction event,<ref name="MacLeod">{{cite journal|author=MacLeod, N, Rawson, PF, Forey, PL, Banner, FT, Boudagher-Fadel, MK, Bown, PR, Burnett, JA, Chambers, P, Culver, S, Evans, SE, Jeffery, C, Kaminski, MA, Lord, AR, Milner, AC, Milner, AR, Morris, N, Owen, E, Rosen, BR, Smith, AB, Taylor, PD, Urquhart, E & Young, JR|title=The Cretaceous–Tertiary biotic transition|year=1997|journal=Journal of the Geological Society|volume=154|issue=2|pages=265–292|url=http://findarticles.com/p/articles/mi_qa3721/is_199703/ai_n8738406/print|doi=10.1144/gsjgs.154.2.0265}}</ref> and more than 90% of [[teleostei|teleost fish]] (bony fish) families survived.<ref>{{cite book |last=Patterson|first=C |year=1993 |title=Osteichthyes: Teleostei. In: The Fossil Record 2 (Benton, MJ, editor) |publisher=Springer |pages=621–656 |isbn=0-412-39380-8}}</ref> There is evidence of a mass kill of bony fishes at a fossil site immediately above the K–T boundary layer on [[Seymour Island]] near Antarctica, apparently precipitated by the K–Pg extinction event.<ref>{{cite journal |title=Discovery of fish mortality horizon at the K–T boundary on Seymour Island: Re-evaluation of events at the end of the Cretaceous |author=Zinsmeister WJ |date=1 May 1998|url=http://jpaleontol.geoscienceworld.org/cgi/content/abstract/72/3/556?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=1&author1=zinsmeister&andorexacttitle=and&field_name=fulltext&searchid=1&FIRSTINDEX=0&sortspec=relevance&fdate=7/1/1927&tdate=7/31/2007&resourcetype=HWCIT |accessdate=2007-08-27 |journal=Journal of Paleontology |volume=72 |issue=3 |pages=556–571 }}</ref> However, the marine and freshwater environments of fishes mitigated environmental effects of the extinction event.<ref name="Robertson">{{cite journal |title= Survival in the first hours of the Cenozoic |author=Robertson DS, McKenna MC, Toon OB, Hope S, Lillegraven JA |journal=GSA Bulletin |year=2004 |volume=116 |issue=5–6 |pages=760–768 |doi=10.1130/B25402.1 |url=http://www.ugcs.caltech.edu/~presto/cenozoic.pdf |format=PDF|accessdate=2007-08-31}}</ref></small>
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! rowspan=3 style="background:#FFFF00" | [[Cenozoico]]
| |||