Verskil tussen weergawes van "Dier"

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Uitgebrei, nog besig
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[[Geen|Genetiese]] studies het ons begrip van die verhouding tussen die diere in Bilateria aansienlik verander. Dit lyk of die meeste tot twee groot stambome behoort: Deuterostomia en Protostomia; laasgenoemde sluit in die Ecdysozoa en Lophotrochozoa. Die Chaetognatha is aanvanklik as Deuterostomia geklassifiseer, maar onlangse molekulêre studies het dié groep geëien as ’n basale Protostomia-lyn.<ref>{{Cite journal|title = Chaetognath phylogenomics: a protostome with deuterostome-like development|url = http://www.cell.com/current-biology/abstract/S0960-9822(06)01835-5 |journal = Current Biology|date = 8 August 2006|issn = 0960-9822|pmid = 16890510|pages = R577–R578|volume = 16|issue = 15|doi = 10.1016/j.cub.2006.07.016|first = Ferdinand|last = Marlétaz|first2 = Elise|last2 = Martin|first3 = Yvan|last3 = Perez|first4 = Daniel|last4 = Papillon|first5 = Xavier|last5 = Caubit|first6 = Christopher J.|last6 = Lowe|first7 = Bob|last7 = Freeman|first8 = Laurent|last8 = Fasano|first9 = Carole|last9 = Dossat}}</ref>
 
Daar is ook ’n paar klein groepe diere met bilaterale simmetrie met relatief kriptiese morfologie waarvan die verwantskap met ander diere nog nie baie duidelik is nie. So het onlangse molekulêre studies Acoelomorpha en ''Xenoturbella'' geëien as behorende tot ’n monofiletiese groep,<ref name="Hejnol">{{cite journal | last1 = Hejnol | first1 = A. | last2 = Obst | first2 = M. | last3 = Stamatakis | first3 = A. | last4 = Ott | first4 = M. | last5 = Rouse | first5 = G. W. | last6 = Edgecombe | first6 = G. D. | display-authors = 6 | last7 = et al | year = 2009 | title = Assessing the root of bilaterian animals with scalable phylogenomic methods | journal = Proceedings of the Royal Society B: Biological Sciences | volume = 276 | issue = | pages = 4261–4270 | doi=10.1098/rspb.2009.0896 | pmid=19759036 | pmc=2817096}}</ref><ref name="Philippe2011" /><ref name="Edgecombe 2011">{{Cite journal|last2=Giribet|first2=G.|last3=Dunn|first3=C. W.|last4=Hejnol|first4=A.|last5=Kristensen|first5=R. M.|last6=Neves|first6=R. C.|last7=Rouse|first7=G. W.|last8=Worsaae|first8=K.|last9=Sørensen|first9=M. V.|year=2011|title=Higher-level metazoan relationships: Recent progress and remaining questions|journal=Organisms Diversity & Evolution|volume=11|issue=2|pages=151–172 |doi=10.1007/s13127-011-0044-4|pmc=|pmid=|last1=Edgecombe|first1=G. D.}}</ref> maar daar is weinig ooreenstemming oor of die groep uitbinne Deuterostomia ontwikkel het,<ref name="Philippe2011">{{Cite journal | last1 = Philippe | first1 = H. | last2 = Brinkmann | first2 = H. | last3 = Copley | first3 = R. R. | last4 = Moroz | first4 = L. L. | last5 = Nakano | first5 = H. | last6 = Poustka | first6 = A. J. | last7 = Wallberg | first7 = A. | last8 = Peterson | first8 = K. J. | last9 = Telford | first9 = M. J. | title = Acoelomorph flatworms are deuterostomes related to ''Xenoturbella'' | journal = Nature | volume = 470 | pages = 255–258 | year = 2011 | pmid = 21307940 | doi = 10.1038/nature09676 |bibcode = 2011Natur.470..255P | issue=7333 | pmc=4025995}}</ref> en of dit ’n sustergroep van alle ander diere met bilaterale simmetrie (Nephrozoa) verteenwoordig.<ref name="Rouse 2016">{{cite journal |last=Rouse |first=Greg W. |last2=Wilson |first2=Nerida G. |last3=Carvajal |first3=Jose I. |last4=Vrijenhoek |first4=Robert C. |date=2016-02-03 |title=New deep-sea species of Xenoturbella and the position of Xenacoelomorpha |url=http://www.nature.com/nature/journal/v530/n7588/full/nature16545.html |journal=Nature |publisher= |volume= 530|issue=7588 |pages=94–97 |doi=10.1038/nature16545 |access-date=2016-02-03 |pmid=26842060|bibcode=2016Natur.530...94R }}</ref><ref name="Cannon 2016">{{cite journal |last=Cannon |first=Johanna T. |last2=Vellutini |first2=Bruno C. |last3=Smith III |first3=Julian. |last4=Ronquist |first4=Frederik |last5=Jondelius |first5=Ulf |last6=Hejnol |first6=Andreas |date=2016-02-03 |title=Xenacoelomorpha is the sister group to Nephrozoa |url=http://www.nature.com/nature/journal/v530/n7588/full/nature16520.html |journal=Nature |publisher= |volume= 530|issue=7588 |pages=89–93 |doi=10.1038/nature16520 |access-date=2016-02-03 |pmid=26842059|bibcode=2016Natur.530...89C }}</ref> Ander groepe met onsekere verwantskap sluit Rhombozoa en Orthonectida in. Een filum, Monoblastozoa, is in 1892 deur ’n wetenskaplike beskryf, maar tot dusver was daar geen verdere bewys dat dit bestaan nie.<ref>[http://www.the-scientist.com/?articles.view/articleNo/32652/title/Gone-Missing--circa-1892/ Gone Missing, circa 1892]</ref>
 
====Deuterostomia en Protostomia====
 
Die [[Ecdysozoa]] behoort tot Protostomia en is genoem na die algemene eienskap van groei deur vervelling.<ref>{{cite book |last=Dawkins |first=Richard |title=The Ancestor's Tale: A Pilgrimage to the Dawn of Evolution |year=2005 |publisher=Houghton Mifflin Harcourt |isbn=978-0-618-61916-0 |page=381}}</ref> Dit sluit die grootste dierfilum, die [[Arthropoda]], in en bevat [[insek]]te, [[spinnekop]]pe, [[krap]]pe, ens. Al dié diere se liggaam is in herhalende segmente verdeel wat gewoonlik in pare voorkom. Twee kleiner filums, Onychophora en Tardigrada, is nabye verwante en deel dié eienskappe. Ecdysozoa sluit ook die [[Nematoda]], of rondewurms, in wat dalk die tweede grootste dierfilum is. Rondewurms is meestal mikroskopies en kom voor in feitlik elke omgewing waar daar water is.<ref>{{cite book |last1=Prewitt |first1=Nancy L. |last2=Underwood |first2=Larry S. |last3=Surver |first3=William |title=BioInquiry: making connections in biology |year=2003 |publisher=John Wiley |isbn=978-0-471-20228-8 |page=289}}</ref> ’n Paar is belangrike parasiete.<ref>{{cite book |title=Parasites in social insects |year=1998 |publisher=Princeton University Press |isbn=978-0-691-05924-2 |last=Schmid-Hempel |first=Paul |page=75}}</ref> Kleiner filums wat aan hulle verwant is, is Nematomorpha, of die perdehaarwurms, Kinorhyncha, Priapulida en Loricifera. Hierdie groepe het ’n klein buikholte, wat ’n skynbuikholte genoem word.
 
[[Beeld:Grapevinesnail 01.jpg|thumb|Die wingerdslak ''Helix pomatia''.]]
 
====Lophotrochozoa====
[[Lophotrochozoa]], wat binne die groep Protostomia ontwikkel het, sluit twee van die mees suksesvolle dierfilums in, [[Mollusca]] en [[Annelida]].<ref>{{cite web |url=http://www.lophelia.org/lophelia/biodiv_6.htm |title=Biodiversity: Mollusca|accessdate=2007-11-19 |publisher=The Scottish Association for Marine Science |archiveurl = https://web.archive.org/web/20060708083128/http://www.lophelia.org/lophelia/biodiv_6.htm |archivedate = 8 July 2006}}</ref><ref>{{cite video | people = Russell, Bruce J. (Writer), Denning, David (Writer) | title = Branches on the Tree of Life: Annelids| medium = VHS | publisher = BioMEDIA ASSOCIATES |year=2000 }}</ref> Eersgenoemde, wat die tweede grootste dierfilum is volgens spesies wat beskryf is, bevat diere soos [[slak]]ke, [[mossel]]s en [[pylinkvis]]se; laasgenoemde die gesegmenteerde wurms, soos [[erdwurm]]s en [[bloedsuier]]s. Hierdie twee groepe is lank as nou verwant beskou omdat hulle soortgelyke larwes het, maar Annelida is as nader aan Arthropoda beskou omdat albei gesegmenteer is.<ref>{{cite journal |last1=Eernisse |first1=Douglas J. |last2=Albert |first2=James S. |last3=Anderson |first3=Frank E. |title=Annelida and Arthropoda are not sister taxa: A phylogenetic analysis of spiralean metazoan morphology |journal=Systematic Biology |volume=41 |issue=3 |pages=305–330 |date=1 September 1992 |doi=10.2307/2992569 |jstor=2992569}}</ref> Nou word dit beskou as saamlopende (maar onafhanklike) evolusie vanweë baie morfologiese en genetiese verskille tussen die twee filums.<ref>{{cite journal |title=Phylogenetic Relationships of Annelids, Molluscs, and Arthropods Evidenced from Molecules and Morphology |journal=Journal of Molecular Evolution |volume=43 |issue=3 |pages=207–215 |publisher=Springer |location=New York |date=September 1996 |doi=10.1007/PL00006079 |pmid=8703086 |last1=Kim |first1=Chang Bae |last2=Moon |first2=Seung Yeo |last3=Gelder |first3=Stuart R. |last4=Kim |first4=Won}}</ref>
 
Lophotrochozoa sluit ook Nemertea, of die snoerwurms, Sipuncula en verskeie filums in wat ’n sirkel tentakels met trilhare om die mond het.<ref>{{Cite book |last=Collins |first=Allen G. |title=The Lophophore |url=http://www.ucmp.berkeley.edu/glossary/gloss7/lophophore.html |year=1995 |publisher=University of California Museum of Paleontology |accessdate=2015-03-23}}</ref>
 
[[Platyzoa]] sluit die filum [[Platyhelminthes]], of die platwurms, in.<ref name="Gilson">{{cite book|last=Gilson|first=Étienne|title=El espíritu de la filosofía medieval|year=2004|publisher=Ediciones Rialp|isbn=978-84-321-3492-0|page=384}}</ref> Hulle is eers as van die mees primitiewe Bilateria beskou, maar dit lyk nou of hulle uit meer komplekse voorouers ontwikkel het.<ref>{{cite journal |last1=Ruiz-Trillo |first1=Iñaki |last2=Riutort |first2=Marta |last3=Littlewood |first3=D. Timothy J. |last4=Herniou |first4=Elisabeth A. |last5=Baguña |first5=Jaume |title=Acoel Flatworms: Earliest Extant Bilaterian Metazoans, Not Members of Platyhelminthes |date=19 March 1999 |journal=Science |volume=283 |issue=5409 |pages=1919–1923 |doi=10.1126/science.283.5409.1919 |pmid=10082465 |bibcode=1999Sci...283.1919R}}</ref> Die groep bevat ’n paar parasiete, soos [[suigwurm]]s and [[lintwurm]]s.<ref name="Gilson" /> Platwurms het nie ’n seloom of buikholte nie, nes hul naaste verwante, die mikroskopiese Gastrotricha.<ref name="umodena">{{cite web |url=http://www.gastrotricha.unimore.it/overview.htm |title=Gastrotricha: Overview |accessdate=2008-01-26 |last=Todaro |first=Antonio |work=Gastrotricha: World Portal |publisher=University of Modena & Reggio Emilia}}</ref> Die ander Platyzoa-filums is meestal mikroskopies en het skynbuikholtes. Die belangrikste groep is [[Rotifera]], of die raderdiertjies, wat algemeen in wateromgewings voorkom. Hulle sluit ook Acanthocephala, Gnathostomulida, Micrognathozoa en moontlik Cycliophora in.<ref name="IntroCyclio">{{cite journal |last=Kristensen |first= Reinhardt Møbjerg |date=July 2002 |title=An Introduction to Loricifera, Cycliophora, and Micrognathozoa |journal=Integrative and Comparative Biology |volume=42 |issue=3 |pages=641–651 |doi =10.1093/icb/42.3.641 |pmid=21708760}}</ref> Hierdie groepe het almal komplekse kake en behoort tot die filum Gnathifera.
 
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