Utente:Marrabbio2/Pesci: differenze tra le versioni
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Riga 558:
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| colspan="3" style="text-align:center; background:#ddf8f8;"| [[Carboniferous]] (359–299 Ma): [[Shark]]s underwent a major [[evolutionary radiation]] during the [[Carboniferous]].<ref name=goldsharks/> It is believed that this evolutionary radiation occurred because the decline of the [[Placodermi|placoderms]] at the end of the Devonian period caused many [[Niche (ecology)|environmental niches]] to become unoccupied and allowed new organisms to evolve and fill these niches.<ref name=goldsharks/>
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Riga 582:
| ''[[Orodus]]'' is another shark of the Carboniferous, a genus from the family [[Orodontidae]] that lived into the early Permian from 303 to 295 Ma. It grew to 2 m (7 ft) in length.
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Riga 591:
| 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}}
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Riga 609:
| 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" />
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Riga 637:
The family [[Ichthyodectidae]] (literally "fish-biters") was a family of marine [[actinopterygii|actinopterygian]] fish. They first appeared 156 Ma during the [[Late Jurassic]] and disappeared during the K-Pg extinction event 65 Ma. They were most diverse throughout the Cretaceous period. Sometimes classified in the primitive [[bony fish]] [[order (biology)|order]] [[Pachycormiformes]], they are today generally regarded as members of the "bulldog fish" order Ichthyodectiformes in the far more advanced [[Osteoglossomorpha]]. Most ichthyodectids ranged between 1 and 5 meters (3–15 ft) in length. All known [[taxa]] were [[predator]]s, feeding on smaller fish; in several cases, larger Ichthyodectidae preyed on smaller members of the family. Some species had remarkably large teeth, though others, such as ''[[Gillicus arcuatus]]'', had small ones and sucked in their prey. The largest Xiphactinus was 20 feet long, and appeared in the Late Cretaceous (below).
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Riga 659:
| 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>
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| colspan="3" style="text-align:center; background:#ddf8f8;"| [[Cenozoic Era]] (65 Ma to present): The current era has seen great diversification of bony fishes. Over half of all living vertebrate species (about 32,000 species) are fishes (non-tetrapod craniates), a diverse set of lineages that inhabit all the world's aquatic ecosystems, from snow minnows (Cypriniformes) in Himalayan lakes at elevations over 4,600 metres (15,000 feet) to flatfishes (order Pleuronectiformes) in the Challenger Deep, the deepest ocean trench at about 11,000 metres (36,000 feet). Fishes of myriad varieties are the main predators in most of the world’s water bodies, both freshwater and marine.
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