Iimfihlelo behlabathi - ixesha Cambrian

Ngokutsho kwinzululwazi esemthethweni, nokuphila kwakuvela kulo mhlaba ngenxa malunga billion emithathu kwiminyaka eyadlulayo ngokohlobo eziphilayo ezilula - iintonga ezincinane ekwanti, izakhiwo filamentary ulele ungqukuva kunye polygonal ezineseli. Ezi eziphilayo lunokubakho kuphela emanzini kwaye kuphela ezishushu.

Ngokubanzi, ukuba yasinda iintsalela ezimbalwa kakhulu ukusuka kwixesha Precambrian. Evolution ubonakala umise ukususela ekuqaleni ubomi iminyaka billion emithathu, ukutshintsha kunye sibufeza iintlobo ezikhoyo kuphela ulwelwe kunye eziphilayo ezincinane.

Noko ke, kwiminyaka million 580 eyadlulayo, kwindawo esitsha kwimbali kwindaleko - ixesha Cambrian. ubude yalo ngaphakathi ubomi Umhlaba lincinane - engama-80 ezigidi. Kungelo xesha ngesiquphe yaye phantse ngaxeshanye kukho iintlobo emangalisayo kweentlobo zezilwanyana ezingenamqolo. Okubaluleke - eziphilayo kwixesha elifutshane bakwazi ukuba zifumane i-calcareous skeleton esiqinileyo.

iintlobo ezininzi bemvelo Cambrian yaba owandulela zonke iintlobo yobomi bale mihla, kuquka abantu. Eli lixesha elinye, ukwenzeka kunye iyantlukwano elibukhali kweentlobo eyaziwa ngokuba dubulo Cambrian.

Umhlaba ngelo xesha kwakukho pustnynyu ngokupheleleyo, bonke ubomi bagxila kuphela emanzini. Amazwekazi zomhlaba waba indawo eyahlukileyo ngokupheleleyo, umzekelo, kwisiza of Greenland nakuMntla Melika yeyona kwilizwekazi Lavrentsov ngasemzantsi nezwekazi waseBrazil. Arabia, Afrika kunye Madagascar baba Afrika emanyeneyo, ibekwe ngasentla lwase Russian, ezahlulwe iStrait of anzongonzongo Siberia kunye ezweni Chinese. Emzantsi, kwakukho nezwekazi omkhulu Australia, apho kamva waya India, Australia kunye nenani iziqithi ahlukana.

Kweli xesha Cambrian kuvele entabeni ethile mihla: Northern Appalachian Mountains, i Sayan Ridge Mountains Chingiztau (Kazakhstan).

Emanzini, yatyatyamba iintyantyambo ngokukhawuleza ubomi: akuba wazinza kwaye trilobites, radiolarians, iziponji, brachiopods. archeocyathids wabonakala - izilwanyana multicellular, nto leyo umnqamlezo phakathi neekorale iziponji. Baya kakhulu zibambene emazantsi imizimba yamanzi, ukwakha uhlobo lezixhobo. Ekupheleni kwale Cambrian, baba saphela.

Ngeli xesha, ingakumbi trilobites kwatyatyamba - arthropods zamandulo ezifana woodlice mihla. Baye umzimba disk-ezimile flat ngezakhe chitinous, yahlulwe ngokwamacandelo 45-50 kunye nobuninzi lemilenze.

Ngasekupheleni kwalo Cambrian kwakukho ezinomqolo kuqala vehicles, AMAGQABAZA ▸ iintlanzi.

Ngoko ke, ngaphandle nawuphi na otshintsho kunye neentlobo eliphakathi ezibophelelayo amagciwane lenyama ehlabathini ngesiquphe kwasekwa iintlobo zezilwanyana ezingenamqolo kunye ezingahlali ezininzi, AMAGQABAZA ▸ iifom mihla. Isithuba Cambrian i jump yokuzivelela zofihlo kwimbali emhlabeni.

Kwiimeko ezininzi abaphandi bathi esi siganeko olwenzeka revolution ebalulekileyo oksijini emoyeni elwandle, kwakunye nokwandisa iityuwa ukuthoba sushi kunye nokwandisa lamanani calcium nezinki emanzini. Khemikhali Ukubunjwa amanzi itshintshile kakhulu ukuba izinto eziphilayo apho, ndafumana ezininzi amathuba utshintsho kwaye ukuyilwa kweentlobo.

Nokuba abonisa ukuba malunga neli xesha, uMhlaba wenze ubhedu ngesiquphe phantse 90 degrees, nto leyo esisizathu sokuba kukho utshintsho olukhulu onke amazwekazi, shifts ziitectonic plates kwaye ukuyilwa uncedo mihla kumphezulu womhlaba. Kwakhona nempembelelo ukuyilwa iintlobo ezintsha kunye sokutshintshwa kwamaphepha emibuzo ukulungiselela basinde.

Amaxesha yendaleko soMhlaba wadibana kakhulu kweentlekele Ngenxa yoko, phantse ngaxeshanye yaye ngaphandle iidayinaso ngaphandle unyamalale kwiminyaka yezigidi-65 eyadlulayo. Kwaye ngeliya xesha localu Permian kwixesha elifutshane ngexesha nye saphela phantse 95% of eziphila elwandle - owawuyiyo kwiminyaka million 245 eyadlulayo.

Kodwa zonke ezi iimfihlelo kuphela ixesha Cambrian yahlukile lokudala wayo, kunokuba kutshatyalaliswe lweentlobo. Abachasi yokusondela yendaleko kubona kwiphazili le Cambrian dubulo ukuqiniswa waphezulu iintlobo mihla ubomi, kuquka abantu.