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1、鸟类真的是恐龙进化而来的吗?鸟类真的是恐龙进化而来的吗?1Newlighthasbeenthrownontheevolutionarylinkbetweenbirdsanddinosaurs.Andit'sfairtosayit'saverystronglink.That'saccordingtoDr.StephenBrusatte,apaleontologistattheUniversityofEdinburg.Heisatthestudytobuildthemostfamilytreeofcarnivorousdinosaursthat'severbeen.
2、Anditleadsfromprehistorictimestotheday.MycolleagueDanDamonaskedhimjusthowcloselyrelatedarethebirdsweseearoundustodinosaurs.Birdsaredinosaursinthesamewaythataretypeofmammalorfrogsaretypeofamphibian.Birds,chickens,hummingbirdstheyareallliving.Howdoyoumakethatlink?Sowehavelotoffossilsnow,awholelotoffos
3、sils.Andwe'vebeenfindingmoreandmoreofthemoverthelast20yearsorso.Thisiswhatustobuildthisbigfamilytree.SomycolleaguesandItraveledaroundtheworldlookingatalotofdinosaurs,puttingtogetherthishugedataset.Thattreeshowsusthattherearesomanyoflivingbirds,thingslikefeathersandwishbones,andwingsthatdidn'
4、tjustevolveinbirds,buttheyevolvedinthedinosaurancestorsofbirds.Ithinkalotofpeoplethinkaboutevolutionintermsoflegs.Youknow,theremustbealinkbetweenmonkeysandmenorbetweendinosaursandbirds.Butthat'snotreallyhowworks.Theevolutionofbirdswasalonggradualprocess,firstfeathersofall,thenwishbones,thenwings
5、.Thenthesedinosaursgotsmaller.Andthentheyputitalltogether.Thebirdbodyplanwasthere.Theywereabletofly.Andthenbang!Somethingwasunlocked;birdstookoff.Andbirdssurvivedthethatkilledoffthedinosaursandtheyarestillaroundtoday,10,000ofthem.Exactly10,000species.Buttheyarebirds.Howdidtheysurvive?Imean,someofthe
6、dinosaursmusthavesurvivedwhenthat,whatwasit,somekindofcomethitFlorida.Andsothatkilledoffmostofthedinosaurs.Almosteverydinosaurdiedexpectforsomebirds.Andwhysomebirdswereabletomakeitthrough?Well,it'sprobablyduetoalotofreasons,butoneofthereasonsisbecausetheycouldfly.Maybebecausetheyweresmaller,they
7、couldgrowfaster.Butaswealsofoundinthisstudy,birdsevolvedfasterthanotherdinosaurs.Oncethatbirdbodyplanoffeathersandwings,andwishbonesallcametogether,itallowedbirdstosimplychangefasterthanothertypesofdinosaurs.Maybethatwasakeytotheirsuccess.第2页 共2页第 2 页 共 2 页第 2 页 共 2 页第 2 页 共 2 页第 2 页 共 2 页第 2 页 共 2 页第 2 页 共 2 页第 2 页 共 2 页第 2 页 共 2 页第 2 页 共 2 页第 2 页 共 2 页