Fuglenes oprindelse: Forskelle mellem versioner

En del tyder på, at fugle stammer fra en bestemte gruppe dinosaurer,<ref>[http://www.sciencedaily.com/releases/2012/05/120530212105.htm The University of Texas at Austin (2012, May 30). Evolution of birds is result of a drastic change in how dinosaurs developed. ScienceDaily] {{Webarchive|url=https://web.archive.org/web/20120601043542/http://www.sciencedaily.com/releases/2012/05/120530212105.htm |date= 1. juni 2012 }} Citat: "..."We looked back approximately 250 million years, to the [[Archosaur]]s, the group which gave rise to crocodiles and alligators as well as modern birds...when we look at birds, we are actually looking at juvenile dinosaurs."..."</ref> og er meget nært beslægtet med [[Familie (biologi)|familien]] ''[[Dromaeosauridae]]''. Fossile rester af Dromaeosaurer og primitive fugle har mange lighedstræk, og derfor bør alle fugle kaldes for 'flyvende dinosaurer'. Fugle stammer altså ikke fra [[flyveøgler]],

<ref>[http://www.dinodatabase.com/dinothry01.asp dinodatabase.com: Flying Dinosaurs] {{Webarchive|url=https://web.archive.org/web/20040620102242/http://www.dinodatabase.com/dinothry01.asp |date=20. juni 2004 }} Citat: "...pterosaurs...were not dinosaurs, although they were related to them; they were flying reptiles..."</ref> som ikke engang var dinosaurer, omend nært beslægtede med [[dinosaur]]er.

<ref>[{{Cite web |url=http://news.bbc.co.uk/hi/english/sci/tech/newsid_1858000/1858574.stm |title=BBCNews, 6 March, 2002, 'Modern' feathers found on Chinese dino] |access-date=13. juni 2009 |archive-date= 3. juni 2002 |archive-url=https://web.archive.org/web/20020603055357/http://news.bbc.co.uk/hi/english/sci/tech/newsid_1858000/1858574.stm |url-status=ok }}</ref>

<ref name="dinohunters">[http://www.dinohunters.com/History/Microraptor.htm dinohunters.com: Microraptor] {{Webarchive|url=https://web.archive.org/web/20090609233421/http://www.dinohunters.com/History/Microraptor.htm |date= 9. juni 2009 }} Citat: "...Microraptor zhaoianus...The discovery of a 130-million-year-old fossil of a feathered dinosaur provides dramatic evidence that birds evolved from the ancient reptiles, according to new research...Theropod dinosaurs and birds share about 100 anatomical features, including a wishbone, swiveling wrists and three forward-pointing toes. Norell said dromaeosaurs were theropod dinosaurs thought to be most closely related to birds..."</ref>

<ref>[http://news.bbc.co.uk/1/hi/world/asia-pacific/4337888.stm 13 October 2005 BBC News: Bird-like dinosaur forces rethink] {{Webarchive|url=https://web.archive.org/web/20071018150013/http://news.bbc.co.uk/1/hi/world/asia-pacific/4337888.stm |date=18. oktober 2007 }} Citat: "...A rooster-sized dinosaur with a long, slender snout and wing-like limbs is forcing a rethink on bird evolution...The authors say the discovery [[Rahonavis]] and [[Buitreraptor]] have long and wing-like forelimbs could imply that flight evolved twice, once in birds and once among this group of [[Gondwana]]n [[dromaeosaur]]s..."</ref>

<ref>[http://www.sciencedaily.com/releases/2005/10/051018071921.htm 2005-10-18, Sciencedaily: Wright Brothers Upstaged! Dinos Invented Biplanes] {{Webarchive|url=https://web.archive.org/web/20051221192524/http://www.sciencedaily.com/releases/2005/10/051018071921.htm |date=21. december 2005 }} Citat: "..."It seems likely that [[Microraptor]] invented the [[biplan]]e 125 million years before the [[Brødrene Wright|Wright]] 1903 Flyer."..."</ref>

<ref>[http://www.ucmp.berkeley.edu/diapsids/dinosaur.html University of California, Berkeley, The Dinosauria: Truth is Stranger than Fiction] {{Webarchive|url=https://web.archive.org/web/20080201133533/http://www.ucmp.berkeley.edu/diapsids/dinosaur.html |date= 1. februar 2008 }} Citat: "...'''Dinosaurs are not extinct'''. Technically. Based on features of the skeleton, most people studying dinosaurs consider birds to be dinosaurs..."</ref>

<ref>[http://www.ucmp.berkeley.edu/diapsids/avians.html University of California, Berkeley: Are Birds Really Dinosaurs?] {{Webarchive|url=https://web.archive.org/web/20030806195929/http://www.ucmp.berkeley.edu/diapsids/avians.html |date= 6. august 2003 }} Citat: "...In fact, the evidence is overwhelmingly in favor of birds being the descendants of a maniraptoran dinosaur...Some researchers today do not agree that dinosaurs gave rise to birds, and are working to falsify this theory, but so far the evidence for the theory has swamped their efforts...."</ref>

<ref>[http://www.birding.com/birdsdino.asp birding.com: Are Birds Dinosaurs?] {{Webarchive|url=https://web.archive.org/web/20041009213655/http://www.birding.com/birdsdino.asp |date= 9. oktober 2004 }} Citat: "...YES they are...NO they are not..."</ref>

<ref>[http://tolweb.org/tree?group=Neornithes&contgroup=Aves Tree of Live web project: Neornithes, Modern Birds] {{Webarchive|url=https://web.archive.org/web/20030803184551/http://tolweb.org/tree?group=Neornithes&contgroup=Aves |date= 3. august 2003 }} Quote: "...Introduction...Whether modern birds are most closely related to dinosaurs or crocodylian ancestors is a point of current debate...."</ref>

<ref>[http://news.bbc.co.uk/1/hi/sci/tech/4187287.stm 20 January, 2005, BBC News: Cretaceous duck ruffles feathers] {{Webarchive|url=https://web.archive.org/web/20060221140936/http://news.bbc.co.uk/1/hi/sci/tech/4187287.stm |date=21. februar 2006 }} Citat: "...Fossil remains of a bird that lived 70 million years ago appear to belong to a relative of modern [[and|ducks]] and [[Gås|geese]]..."This is basically an unidentifiable bundle of bones," Alan Feduccia, a bird expert from the University of North Carolina, US, said...And now all of a sudden it's a modern duck..."</ref>

<ref>[http://news.bbc.co.uk/2/hi/science/nature/5166518.stm 11 July 2006, Big dinosaurs 'had warmer blood'] {{Webarchive|url=https://web.archive.org/web/20190412102356/http://news.bbc.co.uk/2/hi/science/nature/5166518.stm |date=12. april 2019 }} Citat: "...The bigger a dinosaur was, the warmer its blood...smallest dinosaurs had temperatures of around 25C, close to environmental temperatures...biggest dinosaurs – had a body temperature of just over 40C...Most animals cannot tolerate body temperatures of above 45C, so [[Apatosaurus]] is both near the upper limit..."</ref>

Der er en lille minoritet af forskere, mest prominent [[John A. Ruben]], som prøver at argumentere for, at fugle ikke nedstammer fra dinosaurer.<ref>[{{Cite web |url=http://scienceblogs.com/tetrapodzoology/2009/07/17/birds-cannot-be-dinosaurs/ |title=Publishing with a hidden agenda: why birds simply cannot be dinosaurs – Tetrapod Zoology<!-- Bot genereret titel -->] |access-date= 8. oktober 2015 |archive-date= 7. november 2020 |archive-url=https://web.archive.org/web/20201107233101/https://scienceblogs.com/tetrapodzoology/2009/07/17/birds-cannot-be-dinosaurs |url-status=ok }}</ref>