I-Cenozoic Era: Konke Okudingeka Ukwazi

Namuhla sizothatha uhambo oluya kokwedlule. Kepha hhayi esikhathini esedlule seminyaka embalwa noma emakhulwini ambalwa edlule. Sizohamba iminyaka eyizigidi ezingama-66 sibuyela emuva kuze kube manje. Futhi yilokho i-Cenozoic kuyisikhathi okwakungokwesithathu sezikhathi ezinkulu emlandweni woMhlaba. Kwakuyisikhathi esaziwa kakhulu lapho amazwekazi athola khona ukucushwa anakho namuhla. Siyakukhumbula lokho izwekazi le-drift theory nama-plate tectonics achaza ukuthi amazwekazi ayahamba.

Ingabe uyafuna ukwazi zonke izici nezenzakalo, kokubili geological and biological, ezenzeke ku-Cenozoic? Kulokhu okuthunyelwe sizokutshela konke ngakho 

Yini iCenozoic?

I-geology, izimbali nezilwane zomhlaba azizinzile ngokuhamba kwesikhathi. Eminyakeni edlule ziyaguquka ngenxa yokuwela kwezinhlobo nezinguquko ezimweni zemvelo. Amadwala, ngakolunye uhlangothi, ahamba namazwekazi, akha futhi abhubhise ngamacwecwe e-tectonic.

Igama elithi Cenozoic livela ku- igama elithi Kainozoic. Yayisetshenziswa yisazi semvelo saseNgilandi UJohn Phillips ukubiza iziqeshana eziyinhloko ze-Phanerozoic Aeon.

Isikhathi seCenozoic sibe ngesinye sezikhathi ezibaluleke kakhulu, ngoba yisikhathi lapho ama-dinosaurs anyamalala khona. Lokhu kuphawule ukuqala kwenguquko emammalia. Ngaphezu kwalokho, amazwekazi athola ukucushwa okugcinwa namuhla futhi izitshalo nezilwane kwavela. Izimo ezintsha zemvelo ezethulwe yiplanethi yethu, ziphoqeleke ukuthi zishintshe yonke i-panorama eyaziwa kuze kube manje.

Ngesikhathi seCenozoic, i-Atlantic Ocean yanda yaba izintaba ze-Atlantic. Amanye amazwe afana ne-India abe nokushaqeka okukhulu kwe-tectonic okwaholela ekwakhekeni kwezintaba zaseHimalaya. Ngakolunye uhlangothi, ipuleti lase-Afrika lahamba laya ohlangothini lwaseYurophu lakha iSwitzerland Alps. Ekugcineni, eNyakatho Melika amaRocky Mountains akhiwa ngezinqubo ezifanayo.

Amatshe ezazikhona kule nkathi zakhiwa emazwenikazi nasemathafeni aphansi, zathola ubulukhuni obuphakeme. Lokhu kungenxa yengcindezi ephezulu edalwa ukungcwatshwa okujulile, i-chemical diagenesis, namazinga okushisa aphezulu. Ngakolunye uhlangothi, ngamadwala asezintabeni ayehola le nkathi. Ngaphezu kwengxenye yawo wonke uwoyela womhlaba kukhishwa edwaleni ledwala elisentabeni.

Izici zenkathi yeCenozoic

Kusukela lesi sikhathi sangena ngokuqedwa kwama-dinosaurs, kube nezinguquko eziningi ezenzeka ezingeni leplanethi. Esokuqala kwaba ukuvela nokwanda kwezilwane ezincelisayo. Ngokungabi nawo ama-dinosaurs njengomncintiswano, angashintsha futhi ahluke. Ukushintshaniswa kofuzo kusize ekwandiseni ukwanda nokuzivumelanisa nezilwane ezincelisayo ezindaweni ezahlukahlukene.

Ngokuvamile, kwakukhona ukunwetshwa kwezilwane kuwo wonke umhlaba. Amapuleti ama-Tectonic ahamba njalo futhi kule nkathi lapho i-Atlantic Ocean yanda khona. Imicimbi ebinokubaluleka okukhulu futhi ebalulekile namuhla yile:

• Kwakhiwa izintaba ezinkulu zomhlaba wonke.
• Kwavela ama-hominid okuqala.
• Ama-cap polar athuthukiswa.
• Izinhlobo zabantu zavela.

Iziphi izinkathi ezihlanganiswa yile nkathi?

Njengoba kuchaziwe ku- isikhathi sokuma komhlaba Isikhathi ngasinye senziwa ngezikhathi eziningana. ICenozoic ihlukaniswe izikhathi ezimbili ezibizwa ngeTertiary neQuaternary. Lezi nazo zihlukaniswe ngezikhathi ezahlukahlukene.

Isikhathi semfundo ephakeme

Lesi yisikhathi sokuqala lapho izinhlobo zokuphila ebusweni nasolwandle zifana nezanamuhla. Njengoba ama-dinosaurs ayenyamalele, izilwane ezincelisayo nezinyoni zazilawula umhlaba. Lokhu kungenxa yokuthi babengenalo uhlobo lokuncintisana. Ngalesi sikhathi, izilwane ezidla utshani, izilwane ezikhanyayo, ama-marsupials, izinambuzane kanye nemikhomo kwakukhona.

Njengoba sishilo ngaphambili, le nkathi nayo ihlukaniswe yaba izinkathi ezahlukahlukene okungukuthi:

• I-Paleocene. Kubonakala ngokupholisa kwamaplanethi ngokwakhiwa okulandelayo kwamakepisi we-polar. IPangea yezwekazi laseNingizimu Afrika yagcina ihlukanisile futhi amazwekazi aqala ukwakheka njengamanje. Izinhlobo eziningi zezinyoni zavela kanye nokwakhiwa kwama-angiosperms. Futhi, iGreenland yasuka eNyakatho Melika.
• Kulungile. Ngalesi sikhathi kwavela izintaba ezinkulu ezishiwo ngenhla. Izilwane ezincelisayo zakhula kakhulu zaze zaba izilwane ezibaluleke kakhulu. Kuvele amahhashi okuqala futhi kwazalwa amazinyane. Ezinye izilwane ezincelisayo ezifana nemikhomo ezijwayele imvelo yasolwandle.
• Oligocene. Lesi yisikhathi lapho amapuleti ama-tectonic aqhubeka nokushayisana akha uLwandle iMedithera. Kwakhiwa izintaba ezinjengezintaba zeHimalaya kanye neAlps.
• Miocene. Zonke izintaba ziqedile ukwakha futhi kwakheka iqhwa le-Antarctic. Lokhu kudale ukuthi isimo sezulu eMhlabeni sibande kakhulu. Izindawo eziningi zotshani zaqhamuka emhlabeni jikelele nezilwane zavela.
• I-Pliocene. Ngalesi sikhathi, izilwane ezincelisayo zafinyelela ezingeni eliphezulu futhi zasakazeka. Isimo sezulu sasibanda futhi somile futhi kwavela ama-hominid okuqala. Izinhlobo ezifana Ama-Australopithecines futhi i Homo habilis  futhi i Homo erectus ekugcineni, okhokho be Homo sapiens.

Isikhathi se-Quaternary

Lesi yisikhathi sesimanjemanje kakhulu esisaziyo. Ihlukaniswe izikhathi ezimbili:

• I-Pleistocene. Kuyaziwa nangokuthi yisikhathi seqhwa ngoba selule isikhathi esingaphezu kwengxenye yesine yobuso bomhlaba. Izindawo lapho iqhwa lingakaze libe khona ngaphambili zambozwa. Ekupheleni kwalesi sikhathi izilwane ezincelisayo eziningi zase zingasekho.
• Holocene. Yisikhathi lapho iqhwa linyamalala khona likhuphula indawo yomhlaba futhi likhulise ithala lezwekazi. Isimo sezulu sifudumele ngobuningi bezitshalo nezilwane. Abantu bayathuthuka futhi baqale ukuzingela nokulima.

Isimo sezulu seCenozoic

I-Cenozoic yayibhekwa njengesikhathi lapho iplanethi ipholile khona. Kwahlala isikhathi eside impela. Ngemuva kokuthi i-Australia ihlukane ngokuphelele ne-Antarctica ngesikhathi se-Oligocene, isimo sezulu saphola kakhulu ngenxa yokuvela kwe I-Antarctic Circumpolar yamanje okhiqize ukupholisa okukhulu koLwandle i-Antarctic.

Ngesikhathi seMiocene kube nokufudumala ngenxa yokukhishwa kwesikhutha. Ngemuva kokuphola kwesimo sezulu, kwaqala izinkathi zokuqala zeqhwa.

Ngalolu lwazi uzofunda okwengeziwe ngomlando weplanethi yethu 