El isikhathi se-quaternary banezigaba eziningana zokuma komhlaba. Namuhla sizogxila esigabeni sokuqala salesi sikhathi. Imayelana ne- I-Pleistocene. Lesi sigaba se-geological sasibonakala ikakhulu ngokuba namazinga okushisa aphansi kuyo yonke iplanethi nokuvela kwezilwane ezincelisayo ezinkulu ezinjenge-mammoth. Ukuqonda kahle konke okubandakanya ukutadisha kwesikhashana kwalesi sigaba sokuma komhlaba, kubalulekile ukwazi kahle ukuthi isikhathi sokuma komhlaba.
Kulesi sihloko sizokutshela konke odinga ukukwazi ngePleistocene.
Izici eziyinhloko
Lesi sikhathi yisethenjwa kusukela kufundwa ukuvela kohlobo lomuntu. Ngesikhathi sePleistocene Kwaba lapho kuvela okhokho bokuqala bomuntu wanamuhla. Ingesinye sezigaba zemvelo ezifundwa kakhulu futhi esinamarekhodi ezinsalela kakhulu. Lokhu kuqinisekisa ukuthi imininingwane etholakele ibanzi futhi inokwethenjelwa.
IPleistocene yaqala cishe Iminyaka eyizigidi ezingama-2.6 futhi iphela ekupheleni kweminyaka yokugcina yeqhwa yenzeka ngo-10.000 BC Ngalesi sikhathi akukaze kube khona ukunyakaza okukhulu kwamazwekazi. Ihlale isesimweni esifanayo.
Njengoba sishilo ekuqaleni kwendatshana, konke lokhu kuhlukaniswa kokuma komhlaba kuye kwabonakala kakhulu ngokuba namazinga okushisa aphansi emhlabeni jikelele. Lokhu kuholele ekulandelaneni kwemijikelezo yeqhwa lapho amazinga okushisa ebekhula futhi ancipha. Lokhu kwaziwa njengezikhathi zokuhlangana. Cishe U-30% wobuso beplanethi yonke wawumbozwe iqhwa ngokungapheli ngalesi sikhathi. Izindawo eziqhubeka nesithwathwa ngokuqhubekayo bekuyizinti.
Ngokuqondene nezilwane, izilwane ezincelisayo ezinjengemammoth, ama-maston kanye ne-megatherium baphila ubuhle babo obukhulu. Lezi zilwane cishe zazibusa iplanethi ngokuba zinkulu. Kwakukhona nokuthuthuka kokhokho bendoda yesimanje ababengo IHomo erectus, iHomo habilis, neHomo neanderthalensis.
I-Pleistocene geology
Ngalesi sigaba kwakungekho msebenzi omningi we-geological. I- Ukukhukhuleka kwezwekazi Kubukeka sengathi izokwehliswa ijubane uma iqhathaniswa nezikhathi ezedlule. Amapuleti ama-tectonic lapho amazwe ahlala khona awenqabile ukuhamba ngaphezu kwamakhilomitha ayikhulu ukusuka komunye nomunye. Cishe ngalesi sikhathi amazwekazi ayesevele esesimeni esifana ncamashi nalesi esinaso namuhla.
Ama-glaciation ayemaningi kakhulu ngalesi sikhathi, i-ember yagcizelela kwimijikelezo eminingana yokwenyuka okuphawulekayo kokwehla kwezinga lokushisa kweplanethi. Lokhu kudale ukuthi izifunda eziningana ezakhe eningizimu zizogcwala iqhwa ngokuphelele. Njengomphumela weqhwa, ubuso bamazwekazi bathinteka ngenqubo ekhukhulayo. Lokhu yilokho okwaziwa ngokuthi ukumodeliswa kweqhwa.
Futhi ulwandle lwehle kakhulu cishe ngamamitha ayi-100. Lokhu kungenxa yokwakheka kweqhwa ngesikhathi seqhwa.
Isimo sezulu sePleistocene
Ngalesi sigaba sokuma komhlaba, yini eyaziwa ngokuthi i- i-ice Age. Lokhu kuyiphutha ngoba ngesikhathi sePleistocene kwenzeka uchungechunge lweqhwa lapho bekuba nezikhathi ezinamazinga okushisa abephakeme ngokwemvelo kanti amanye aphansi. Isimo sezulu emazingeni okushisa asezingeni elifanele sasishintsha njalo phakathi nenkathi yize amazinga okushisa azange zikhuphuke kakhulu njengakwezinye izikhathi zokwakheka komhlaba.
Izimo zezulu cishe ziwukuqhubeka kwenkathi yangaphambili yePliocene. Kulesi sigaba amazinga okushisa eplanethi ehle kakhulu. Imigqa yomhlaba eseduze nezigxobo yabonwa, futhi phakathi nalesi sigaba i-Antarctica yahlala icishe yagcwala iqhwa ngokuphelele emaphethelweni asenyakatho yezwekazi laseMelika nelaseYurophu ngesikhathi seqhwa.
Kusona sonke isigaba sePleistocene kwakukhona izinguzunga ezine.
Izimbali, izilwane nezilwane
Ngalesi sigaba, impilo yayihluke kakhulu naphezu kwakho konke ukulinganiselwa kwesimo sezulu okwakukhona ngenxa yeqhwa. Ngesikhathi sePleistocene kwakukhona eziningana izinhlobo zama-biomes. Kuhlobo ngalunye lwe-biome, izitshalo ezingakwazi ukuzivumelanisa kangcono nezimo ezimbi kakhulu zakhiwa. Engxenyeni esenyakatho yeplanethi ngaphakathi kwe-Arctic Circle kulapho i-biome esiyazi namuhla njenge-tundra yathuthuka khona. Izici eziyinhloko ze-tundra yilokho izitshalo zincane, azikho izihlahla ezinamaqabunga noma ezinkulu. Kulolu hlobo lwemvelo, ubulembu buningi.
I-taiga futhi ingenye i-biome eyabonwa ngesikhathi sePleistocene. I-taiga iqukethe ikakhulukazi uhlobo lwemifino lapho kudla khona kakhulu izihlahla ze-coniferous futhi kwesinye isikhathi zifinyelela ezindaweni eziphakeme kakhulu. Njengoba imininingwane ikhishwe kumarekhodi ezinsalela, kwakukhona nobulembu, ubulembu namanye amafern kula ma-biomes.
Ngaphakathi kwamazwekazi izinga lokushisa lalingephansi kangako futhi lavumela izitshalo ezinkulu ukuba zikhule ezazingakha amahlathi amakhulu. Kulapha lapho kwaqala khona ukuvela izitshalo ze-thermophilic. Lezi zitshalo yilezo ezinokuzivumelanisa nezimo obekudingeka ukuze zisinde emazingeni aphezulu okushisa.
Ngokuya ngezilwane, izilwane ezincelisayo kwakuyiqembu elalikhonya kakhulu. Okunye okuvelele ngalezi zilwane ukuthi kwaziwa njenge-megafauna. Lokho wukuthi, izilwane ezivelele zazizinkulu futhi zikwazi ngokuphelele ukumelana namazinga okushisa aphansi ayekhona ngaleso sikhathi.
Ngaphezu kwalokho, amanye amaqembu ezilwane aqhubeke nokwandisa ukwehluka kwawo nokuziphendukela kwemvelo ukujwayela izindawo ezintsha. Lezi zilwane yizinyoni, izilwane eziphila ezweni nasemanzini, nezilwane ezihuquzelayo. Umammoth wayeyisilwane esincelisayo esithakazelisa kakhulu ngalesi sikhathi. Ukubukeka noma zazifana ncamashi nezindlovu esizaziyo namuhla. Babenamazinyo amade abukhali futhi isici sabo esikhulu kwakuwukugoba okubabhekise phezulu. Ngokuya ngendawo lapho zizotholakala khona nezinga lokushisa lazo lalimbozwe ngoboya obuningi noma obuncane futhi babenomkhuba wokudla okweqile.
Ngokuqondene nabantu, iningi lohlobo lwamadlozi lwe Homo sapiens kodwa nayo le yabonakala. Isici sayo esiyinhloko ukuthi yafinyelela ekukhuleni okuphelele kobuchopho bayo.
Ngiyethemba ukuthi ngalolu lwazi ungafunda kabanzi ngePleistocene.