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<noinclude>{{rpsv.from.wpsv}}</noinclude> {{Taxobox | name = Neornithes | fossil_range = [[Krita]] - nutid | domain_sv = [[Eukaryoter]] | domain = Eukaryota | regnum_sv = [[Djur]] | regnum = Animalia | phylum_sv = [[Ryggsträngsdjur]] | phylum = Chordata | subphylum_sv = [[Ryggradsdjur]] | subphylum = Vertebrata | classis = [[Aves]] | classis_sv = [[Fåglar]] | subclassis = '''Neornithes''' | subclassis_authority = [[Hans Friedrich Gadow|Gadow]], 1893 | subdivision_ranks = Överordningar | subdivision = [[Paleognathae]]<br/> [[Neognathae]]<br/> }} Underklassen '''Neornithes''', ibland kallade '''nutida fåglar''' är arter av klassen [[Aves]] som har överlevt fram till historisk tid. Nutida fåglar karakteriseras främst av sin tandlösa [[näbb]] då merparten av gruppen [[förhistoriska fåglar]] hade just tandförsedda näbbar. <!-- Many species of modern bird undertake long distance annual [[bird migration|migrations]], and many more perform shorter more irregular movements. They are primarily [[Varieties of Monogamy|socially monogamous]], with engagement in [[non-human animal sexual behavior|extra-pair copulations]] being common in some species; other species have [[polygamy|polygamous]] or [[polyandry|polyandrous]] breeding systems. Eggs are usually laid in a [[nest]] and [[Avian incubation|incubated]] and most birds have an extended period of parental care after hatching. --> ==Taxonomi== Nutida fåglar delas upp i två [[överordning]]ar, [[paleognata fåglar]] (Paleognathae) vilket är en mindre grupp där merparten saknar flygförmåga, och den större gruppen [[neognata fåglar]] (Neognathae) som är mycket variationsrik och omfattar resterande arter. Allmänt anses Neornithes ha utvecklats under [[Krita]]-perioden och uppdelningen av de båda [[klader]]na [[Galloanserae]] (den grupp som bland annat omfattar [[Anseriformes]]) och övriga neognata fåglar skedde före [[Krita/Tertiär-gränsen|Krita-Tertiär-utdöendet]] för cirka 65,5 miljoner år sedan. Dock råder det delade meningar kring huruvida följande uppdelning i klader skedde före eller efter de övriga dinosauriernas utdöende.<ref name = "Ericson">Ericson PGP, Anderson CL, Britton T, Elzanowski A, Johansson US, Kallersjo M, Ohlson JI, Parsons TJ, Zuccon D, Mayr G (2006)"Diversification of Neoaves: integration of molecular sequence data and fossils" ''Biology Letters'' '''2'''(4): 543-547</ref><!-- This disagreement is in part caused by a divergence in the evidence, with molecular dating suggesting a Cretaceous radiation and [[fossil]] evidence supporting a [[Tertiary]] radiation. Attempts made to reconcile the molecular and fossil evidence have proved controversial.<ref name = "Ericson"/><ref>Brown J, Payne B, & Mindell D (2006) "Nuclear DNA does not reconcile 'rocks' and 'clocks' in Neoaves: a comment on Ericson ''et al.'' ''Biology Letters'' '''3''' 1-3</ref> The classification of modern birds is a contentious issue. [[Charles Sibley|Sibley]] & Ahlquist's ''Phylogeny and Classification of Birds'' (1990) is a landmark work on the classification of birds, although frequently debated and constantly revised. A preponderance of evidence seems to suggest that the modern bird orders constitute accurate [[taxon|taxa]]. However, scientists are not in agreement as to the relationships between the orders; evidence from modern bird anatomy, fossils and DNA have all been brought to bear on the problem but no strong consensus has emerged. More recently, new fossil and molecular evidence is providing an increasingly clear picture of the evolution of modern bird orders. See also: [[Sibley-Ahlquist taxonomy]] and [[dinosaur classification]]. --> ''För klassificering se artikeln [[fåglar]]'' ===Fylogeni=== Nutida fåglars [[basal]]a klader baserat på [[Sibley-Ahlquists taxonomi]]. {{clade |label1='''Neornithes'''&nbsp;&nbsp; |1={{clade |label1=[[Paleognathae]]&nbsp; |1={{clade |1=[[Struthioniformes]] |2=[[Tinamiformes]] }} |label2=&nbsp;[[Neognathae]]&nbsp; |2={{clade |1=[[Neoaves]] |label1=&nbsp; |label2=[[Galloanserae]]&nbsp; |2={{clade |1=[[Anseriformes]] |label2=&nbsp;&nbsp;&nbsp;&nbsp; |2={{clade |1=[[Galliformes]] |2=[[Craciformes]] }} }} }} }} }} ==Referenser== ===Noter=== <references/> ===Källa=== {{artikelursprung| källa=engelskspråkiga Wikipedia| url=http://en.wikipedia.org/w/index.php?title=Modern_birds&oldid=222471876| artikel=Modern Birds| datum=2008-07-18| bild= }} [[Kategori:Fåglar]] [[de:Neornithes]] [[en:Modern birds]] [[es:Neornithes]] [[fr:Neornithes]] [[it:Neornithes]] [[nl:Neornithes]] [[nn:Moderne fuglar]] [[oc:Neornithes]] [[pl:Neornithes]] [[pt:Neornithes]]

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