Dinosaur

Bacewa a cikin Cretaceous, shekaru miliyan 65 da suka wuce, dinosaur sun dauki hankali daga mafi ƙanƙanta ga masana burbushin halittu na dinosaur. Ba abin mamaki bane, tunda halittu ne masu manyan fikafikai cewa duk muna son yin tunanin yadda wata rana suka yi yawo cikin yardar rai a cikin duniyarmu. Asalinsa ya koma kusan shekaru miliyan 240/230 da suka wuce, shi ya sa suke zama kashin baya. rinjaye a Duniya tsawon shekaru miliyan 165-175.

Ko da yake Kalmar dinosaur tana nufin "mummunan kadangaru" (wanda Richard Owen ya tsara), ba su kasance kamar dabbobi masu rarrafe ba kamar yadda muka san su a yau. A haƙiƙa, hanyar tafiyarsu ta kasance ta biyu ne, kuma ko da bincike na baya-bayan nan ya nuna cewa za su iya zama dabbobi masu ɗumi. Tare da haɓakar haɓakawa mai yawa, nesa da abin da za a sa ran daga babban dabba, za su kasance da sauri kuma sun dace da sauri zuwa canje-canje fiye da yadda ake tsammani. Ko da, ƙila sun haɓaka dabarun zamantakewa, wanda ya sanya su zama a cikin garken shanu. Dalilin da zai bayyana hanyar da aka gano da yawa daga cikin burbushinsa.

Takaitaccen bayani na farkon da bayyanar dinosaurs

Dinosaurs sun bayyana a ƙarshen lokacin Triassic. Su ne zuriyar archosaurs, irin waxanda suke fitowa daga cikin kada da tsuntsaye. Sun taso ne shekaru miliyan 20 bayan babban taro na Permian - Triassic, wanda ya shafe 95% na rayuwar da ta wanzu a duniya. Ba a tabbatar da abin da ya haifar da wannan bacewar ba, amma rayuwa ta dauki lokaci mai tsawo kafin ta farfado saboda gagarumin tasirin da ta yi.

Zamanin da suka wanzu shine Mesozoic.Har ila yau, an san shi da shekarun dinosaur. Ya kara daga 225 zuwa 65 shekaru miliyan da suka wuce. Ya mamaye wani ɓangare na Triassic, da duk Jurassic da Cretaceous. Ɗaya daga cikin dinosaur na farko shine Eoraptor, mai bipedal mafarauci. Ana ɗauka a matsayin kakan gama-gari na dukan dinosaur da suka taɓa wanzuwa. A lokacin Jurassic, zamu iya samun wasu dinosaur da aka sani da Diplodocus, wanda ya wanzu tsakanin shekaru 156 zuwa 145 da suka wuce. Shahararren Tyrannosaurus Rex yana daya daga cikin jinsin karshe da suka wanzu Maimakon haka, ya rayu a ƙarshen Cretaceous, tsakanin shekaru 68 da 66 da suka wuce.

A lokacin, yanayin ya yi zafi fiye da yadda yake a yau. Kimanin digiri 10 mafi girma. Matsakaicin adadin carbon dioxide sau 4 mafi girma, mai yiwuwa saboda fashewar volcanic da ya wanzu. Bangaren ƙasa, duk sun haɗu a cikin nahiya guda ɗaya, Pangea, ba ta haifar da gaɓar teku da yawa ba, don haka tasirin tekun bai wanzu ba. Yanayin nahiya ya sanya lokacin rani yayi zafi sosai, damina kuma yayi sanyi sosai.

Yaya dinosaurs suke?

Duk bayanan da aka tattara a yau sun fito ne daga bayanan burbushin halittu. Daga cikin su za su iya zama ƙashi ko a'a, kamar sawun ƙafa, ɗigon ruwa, fuka-fukai, ra'ayin fata, da laushin kyallen takarda da gabobin ciki. Hakanan, don fahimtar da kuma gano halayensu da ilimin halittu, fannonin kimiyya daban-daban suna shiga cikin wasa. Biology, chemistry, physics da paleontology galibi. Daga cikin su duka, daga rubuce-rubucen da aka samo, yin la'akari da ilimin da muke da shi a yau na sauran dabbobi masu rarrafe, tsuntsaye, har ma da ilimin kimiyyar lissafi don ayyana su na biomechanics, za mu iya fahimtar yadda suke.

Yaya girman dinosaurs?

An lura da cewa girman dinosaur ya canza tsakanin lokuta daban-daban wanda ya wanzu da kuma yankin. Misali, kashi 80 cikin 1877 na dinosaur da aka samu a Morrison Formation, a yammacin Amurka da kuma inda aka samu burbushin farko a 20, suna da Stegosaurus da sauropods. Na karshen yana da matsakaicin matsakaicin nauyin ton XNUMX, kasancewar dinosaur mafi girma da aka taɓa samu. Burbushin da aka samu a wurin na Jurassic ne.

Duk da haka, binciken da aka yi a baya-bayan nan irin na 2015 ya nuna cewa girman dinosaur ya riga ya girma fiye da yadda ake tunani a baya. Duk wannan ne sakamakon wani bincike da aka yi a kasar Argentina a shekarar 2015. An gano wani sabon kwarangwal din Dinosaur, watau Ingentia Prima. An kiyasta cewa ya wanzu tsakanin shekaru miliyan 228 zuwa 201 da suka wuce, a cikin Triassic. An kuma kiyasta cewa girmansa zai kasance kusan mita 8 zuwa 10 a tsayi, tare da matsakaicin nauyin tan 9. Wannan sabon layin yana bayyana cewa a juyin halitta, Dabarar da ta sa dinosaur su zama kattai sun kasance da wuri fiye da tunani, a gaskiya, kusan tun daga farko ne suka fara wanzuwa. Matsalolin wannan binciken shine cewa an yi imani cewa a farkon su ƙanana ne, lokacin da gaske Ingentia Prima shine dalilin cewa wannan imani ba haka yake ba.

Yawancin burbushin ba a tono su ba, kuma galibin nau'in dinosaur da suka wanzu ba a samo su ba ko kuma ba a samu ragowar su ba. Girman su ya zama mai canzawa sosai, kamar gigantic Argentinosaurus, Puertasaurus ko kwanan nan da aka samu. Patagotitan, wanda girmansa ya kai mita 40 kuma yayi nauyin ton 70. Wasu kuma, ƙananan ƙananan ne, irin su Compsognathus, wanda aka yi imanin a shekarun 90 shine mafi ƙarancin dinosaur, tsayinsa ya kai mita 1 kuma yana da nauyin kilo 3-4. Kwanan nan, duk da haka, sabbin abubuwan da aka gano sun ɗauke "shugabanci", har ma an gano ƙananan nau'ikan. Misali, da Hesperonychus, wanda girmansa ya kai santimita 50, nauyin kilogiram 2, da kuma nau'in halitta mai kama da Compsognathus.

halin dinosaur

Kamar yadda tsuntsaye, crocodiles, da dinosaur suka sauko daga archosaurs, akwai yarjejeniya mai kyau cewa yawancin dabi'un dabi'a na kowa. Misali, tsuntsaye da halayensu na zamantakewa suna zaune a cikin garke. Fassarar wannan suna da goyon bayan hanyar da aka samu burbushin halittu da yawa, yanayin kwarangwal, wurin zama, da kuma simintin halittu ta hanyar kwamfuta.

Este halin garken Wannan ya bayyana a fili lokacin da a cikin 1878 31 Iguanodon kwarangwal aka samu tare a Belgium. Bayan dalilan da suka haifar da mutuwar rukuni, ko sun fadi, ganima ga wani dinosaur, da dai sauransu. Abin ban sha'awa shi ne cewa ana yawan samun ajiya tare da kwarangwal iri ɗaya. Bugu da kari, wani daga cikin alamomin shi ne na sawun burbushin halittu, wadanda ke tabbatar da wannan dabi'a mai girman gaske da zamantakewa.

Ƙwararru da ruffs na wasu dinosaur sun nuna cewa za a iya amfani da su a matsayin hanyar lalata da kuma jima'i.

A gefe guda, hare-hare tsakanin dinosaur sun kasance ruwan dare. An gano ragowar cizon wutsiya, har ma akwai burbushin halittu irin na Velociraptor da ke kai hari kan Protoceratops. Wasu burbushin halittu ma suna nuna cewa cin naman mutane tsakanin wasu nau'in na iya wanzuwa. Duk da haka, wasu halaye sun bambanta sosai a tsakanin su, ya danganta da wurinsu, abincinsu, girmansu, wurin tafiya, da sauransu. Wani abu da ake nunawa, bisa ga jinsin da muke magana akai.