— inothi lensimu No. 8 —
I-Triassic, i-Jurassic ne-Cretaceous: izikhathi ezintathu ze-Mesozoic
Impendulo emfushane
I-Tyrannosaurus iseduze nathi ngesikhathi kunokuba yayiseduze ne-Stegosaurus. Lokhu akulona ihlaya, yizibalo nje: inkathi ye-Mesozoic yathatha cishe iminyaka eyizigidi ezingu-186, futhi ihlukaniswe yaba izikhathi ezintathu, i-Triassic, i-Jurassic ne-Cretaceous. Phakathi naleso sikhathi kwavela amadayinaso, i-Pangaea yaqhekeka, futhi izitshalo nezilwane zashintsha kaningana.
Inkathi eyodwa, imihlaba emithathu
Kumafilimu, amadayinaso azo zonke izikhathi adla otshanini endaweni eyodwa. Empeleni i-Stegosaurus yasekupheleni kwe-Jurassic ne-Tyrannosaurus yasekupheleni kwe-Cretaceous zihlukaniswa yiminyaka engaphezu kwezigidi ezingu-80, okungaphezu kwalokho okuhlukanisa i-Tyrannosaurus nathi. Ngemuva kwegama elithi “Mesozoic” kunomlando omude kakhulu futhi oxubile kakhulu.
Ukuze ungalahleki kuwo, gcina eduze umugqa wezikhathi kanye nemephu yomhlaba wasendulo. Owokuqala ubonisa ukuthi yini eyalandela yini. Eyesibili ikukhumbuza ukuthi amazwekazi ayengahlali njalo lapho sejwayele ukuwabona khona.
I-Triassic: amadayinaso angena esiteji
Isikhathi se-Triassic sasukela cishe eminyakeni eyizigidi ezingu-252 kuya ku-201 edlule. Cishe wonke umhlaba owomile wawuhlangene waba yizwekazi elilodwa elikhulukazi, i-Pangaea. Phakathi nendawo kulo, kude nolwandle, ezindaweni eziningi kwakomile, nakuba isimo sezulu sasihluka kusukela kolunye uhlangothi kuya kolunye.
Izinsalela zamadayinaso zakudala kunazo zonke ezingangatshazwa zingezasekupheleni kwe-Triassic, futhi zineminyaka ecishe ibe yizigidi ezingu-230; iqembu ngokwalo kungenzeka lavela ngaphambidlana. Ngaleso sikhathi amadayinaso ayengakabi ngabaphathi bomhlaba owomile, ayesezindimeni zesibili. Nge-Triassic futhi kwandiza ama-pterosaur okuqala. Isikhathi saphela ngokushabalala okukhulu, ngemva kwalokho izilwane zomhlaba zahluka ngokuphelele.
I-Jurassic: izilwane ezinkulukazi nezinyoni zokuqala
Isikhathi se-Jurassic sasukela cishe eminyakeni eyizigidi ezingu-201 kuya ku-143 edlule. Ingxenye yaso yokugcina yasinika uhlu lwezilwane ezidumile: i-Brachiosaurus, i-Diplodocus, i-Stegosaurus ne-Allosaurus edla inyama. Ngaleso sikhathi futhi kwakuphila i-Archaeopteryx, inyoni yakuqala eyayinezici zamadayinaso adla inyama. Ngo-2025 kwachazwa enye inyoni ye-Jurassic evela eShayina, i-Baminornis, esivele inomsila omfushane njengezinyoni zanamuhla.
Phakathi kwezilwane ezinkulu ezizingelayo zaleso sikhathi kufanele ukhumbule ne-Torvosaurus. Ngaleso sikhathi i-Pangaea yayiqhekeka, kuvuleka izilwandle ezintsha phakathi kwezingxenye zayo. Amazwekazi anyakaza kancane, kodwa ezigidini zeminyaka lokho kwanele ukuhlukanisa izilwane ziye emaceleni ahlukene olwandle.
I-Cretaceous: izimbali, ubuso obusha nokuphela kwenkathi
Isikhathi se-Cretaceous yisona eside kunazo zonke kulezi ezintathu, sisukela cishe eminyakeni eyizigidi ezingu-143 kuya ku-66 edlule. Ngaleso sikhathi izitshalo ezinezimbali zasabalala kakhulu emhlabeni owomile. Amadayinaso ayemaningi futhi ehlukahlukene kakhulu, kodwa izilwane ezidume kakhulu, i-Tyrannosaurus ne-Triceratops, zavela ngasekugcineni impela.
Ikhethini lehla eminyakeni eyizigidi ezingu-66 edlule: emngceleni we-Cretaceous ne-Paleogene kwaba nokushabalala okukhulu, futhi onke amadayinaso angezona izinyoni anyamalala. Okwenzeka ngempela kuchazwa enothini elikhuluma ngokushabalala kwamadayinaso. Izinyoni zasinda kule nhlekelele, okuwukuphela kwegatsha lamadayinaso elafika ezikhathini zethu.
Imibuzo nezimpendulo
Yisiphi isikhathi se-Mesozoic esasiside kunazo zonke?
I-Cretaceous, cishe iminyaka eyizigidi ezingu-77. I-Jurassic yathatha cishe izigidi ezingu-58, i-Triassic cishe ezingu-50. Imingcele lapha isondeziwe.
Ingabe i-Tyrannosaurus ne-Stegosaurus zaphila ngesikhathi esisodwa?
Cha. I-Stegosaurus yaziwa ekupheleni kwe-Jurassic, i-Tyrannosaurus ekugcineni impela kwe-Cretaceous. Phakathi kwazo kunengaphezu kweminyaka eyizigidi ezingu-80.
Amadayinaso okuqala avela nini?
Amadayinaso akudala kunawo wonke angangatshazwa aneminyaka eyizigidi ezingu-230–233, okusho ukuphela kwe-Triassic. Iqembu ngokwalo mhlawumbe lidala kancane. Ngo-2025 kwachazwa i-Ahvaytum, idayinaso elincane elivela e-Wyoming elineminyaka ecishe ibe yizigidi ezingu-230: kusho ukuthi enyakatho ye-Pangaea amadayinaso ayephila cishe kusenesikhathi njengaseningizimu.
Ameva asemsileni we-Stegosaurus abizwa ngokuthini?
I-thagomizer. Leli gama laqanjwa ngo-1982 ngumdwebi wamakhathuni u-Gary Larson, izazi zezinsalela zalithatha njengehlaya, kanti manje litholakala nasemaphepheni esayensi nasemnyuziyamu.
