U fiirso qoraalka hoose ka dibna ka jawaab su'aasha kadib isla luqadda qoraalka:  Marinka: Dinosaur-yadu waxay ka soo baxeen awoowayaashood archosaur intii lagu jiray bartamihii illaa dhammaadkii xilligii Triassic, qiyaastii 20 milyan oo sano ka dib dhacdadii dabar go'a Permian-Triassic oo tirtirtay qiyaastii 95% dhammaan nolosha dhulka. Taariikhda radiometric ee dhismaha dhagaxa oo ay ku jireen lafdhabarta laga soo qaatay dinosaur-kii hore ee noociisu ahaa Eoraptor 231.4 milyan oo sano jir ah ayaa aasaasaya joogitaankiisa diiwaanka lafdhabarta waqtigan. Khubarada cilmiga noolaha waxay u maleynayaan in Eoraptor uu la mid yahay awoowayaashii diinoosaarada oo dhan; haddii ay taasi run tahay, astaamaheeda waxay muujinayaan in diinoosaaradii ugu horreeyay ay ahaayeen kuwo yaryar, ugaadhsadeyaal laba lugood leh. Aragtidaas waxaa taageeraya helitaanka asalka ah, dinosaur-sida ornithodirans sida Marasuchus iyo Lagerpeton ee Argentina ee Triassic Strata dhexe; falanqaynta burburka la soo saaray waxay soo jeedineysaa in xayawaankan ay runtii ahaayeen kuwo yaryar, ugaarsadayaal laba lugood leh. Diinoosaaradu waxay u badan tahay inay soo baxeen horaantii 243 milyan oo sano ka hor, sida ay caddeeyeen haraadiga jilibka Nyasasaurus ee xilligaas, in kasta oo lafdhabarta loo yaqaan ee xayawaankan ay aad u jajaban yihiin si loo sheego inay yihiin dinosaur ama qaraabo aad u dhow oo dinosaur ah. Dhawaan, waxaa la ogaaday in Staurikosaurus oo ka soo jeeda Santa Maria Formation uu jiray 233.23 Ma, taasoo ka dhigeysa da'da geolojiga ee ka weyn Eoraptor. Markii dinosaursku soo muuqdeen, ma aysan ahayn xayawaanka dhulka ku nool. Meelaha dhulka lagu noolaado waxaa ku noolaa noocyo kala duwan oo ah archosauromorphs iyo therapsids, sida cynodonts iyo rhynchosaurs. Tartamayaashooda ugu waaweynaa waxay ahaayeen pseudosuchia, sida aetosaurs, ornithosuchids iyo rauisuchians, kuwaas oo ka guulaystay dinosaurs. Badanaa xayawaanadaasi waxay dabar go'een Triassic, laba dhacdo midkood. Ugu horeyn, qiyaastii 215 milyan oo sano kahor, noocyo kala duwan oo ah archosauromorphs, oo ay ku jiraan protorosaurs, ayaa dabar go'ay. Tan waxaa soo raacay Triassic-Jurassic (qiyaastii 200 milyan oo sano ka hor), taas oo ay ku dhammaadeen inta badan kooxaha kale ee hore ee archosaurs, sida aetosaurs, ornithosuchids, phytosaurs, iyo rauisuchians. Rhynchosaurs iyo dicynodonts ayaa badbaaday (ugu yaraan...  Su'aal: Daanyeer noocee ah ayay aqoonyahanada cilmiga dhirta iyo xayawaanku aaminsanyihiin in uu yahay nooca ugu caansan?
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