La Isikhathi seCenozoic iqala nge Isikhathi sePaleogene y ukuhlukaniswa kwesilinganiso sesikhathi se-geologic. Iqale ke le nkathi ebihlanganisa iminyaka eyizigidi ezingama-66 edlule futhi yaphela cishe eminyakeni eyizigidi ezingama-23 edlule. Le nkathi yesikhathi ukuvela kwezilwane ezincelisayo kwakuphawuleka impela yize kwakudingeka zivele ezinhlotsheni ezincane. Lezi zinhlobo zazincane uma siziqhathanisa nama-dinosaurs ayekhona ku isikhathi se-cretaceous.
Kulesi sihloko sizokutshela zonke izici, i-geology, isimo sezulu, izimbali nezilwane zesikhathi sePaleogene.
Izici eziyinhloko
Igama elithi Paleogene livela ezinhlotsheni zakudala kakhulu zempilo yakamuva. Lapho sikhuluma ngempilo yakamuva sigcizelela konke okukhona kusukela enkathini yeCenozoic. Ekuqaleni kwePaleogene kwakukhona ukuphazamiseka lapho kukhulunywa no Izinga lokuma komhlaba ngemuva kokuqothulwa kwama-dinosaurs ekugcineni kweCretaceous.
Ngalesi sikhathi iNyakatho Melika neGreenland ekugcineni bahlukaniswa nezwekazi lase-Eurasia. Ngenxa yalokhu, uLwandle lwaseNorway lwakhiwa. Lolu lwandle lukhona cishe iminyaka eyizigidi ezingama-60. Ngaleso sikhathi ezinye izilwandle zazihamba ngendlela yazo, njengolwandle i-Indian kanye ne-Atlantic. Ngenxa yalokhu, likwazile ukunweba ngendlela yokuthi izinhlobo zezitshalo nezilwane zikwazi ukuguquka ngazinye. Lokhu kungenxa yokuthi uhlobo ngalunye lwalushintshelwe esimisweni semvelo esihlukile.
Ngenxa yalezi zimo ezahlukahlukene zemvelo, lolu hlobo lukhiqiza ukujwayela okuhlukahlukene ukuze luphile emvelweni.
I-Paleogene Geology
Uma singabhekisi e-Australia nase-India siyabona ukuthi bebehamba beya ngasenyakatho-mpumalanga ngenxa yokuhamba kwezwekazi. Isivinini esilinganisiwe sokuhamba kwalawa mazwekazi sasicishe sibe ngamasentimitha ayi-6 ngonyaka. Njengoba kufakazelwe izifundo zakamuva ze-geological, izinga lokwehla kwezwekazi lehle kakhulu ngokuhamba kwesikhathi.
Lokhu kufuduka ohlangothini olusenyakatho-mpumalanga kubangele noma ukuhlukaniswa kwe-Antarctica eyasala duzane nensika yaseningizimu ukusuka kwimvelaphi yePangea. Eminyakeni engaba yizigidi ezingama-40 kamuva, i-India yayivele icishe yahlukaniswa ngokuphelele ne-Afrika futhi yayizoshayisana ne-Asia ukuhlangana kwakhiwe Himalaya. Ukushayisana nokwakhiwa kwezintaba zaseHimalaya kwakuyimbangela yokuvala ulwandle lolwandle olukhulu iTethys. Lokhu kwenzeka cishe eminyakeni eyizigidi ezingama-52 edlule.
Izinguquko esimweni sezulu
Sonke isikhathi sePaleogene kube nezinguquko zesimo sezulu ezinzima njengokupholisa ezindaweni ezibandayo. Ngaleso sikhathi, ukwakheka kwamalahle nokwakheka komhlaba njenge-Alps kanye nohlu olubanzi lwezintaba zase-Andean eNingizimu Melika nakho kwaqala.
Lokhu kuphola akubonanga iplanethi yethu ngemuva kokuqothulwa kwe- I-Triassic. Ngenxa yokwehla kwamazinga okushisa omhlaba, ukuvunyelwa kwesikhashana komhlaba wonke kwavunyelwa. Noma kunjalo, Ngenkathi isikhathi sePaleogene siqhubeka, izinga lokushisa lomhlaba lakhuphuka futhi. Ngenxa yalokhu kwanda kwamazinga okushisa, umhlaba waqala waba yindawo eshisayo ezindaweni eziningi. Kulezi zindawo isimo sezulu sasihluke ngokuphelele kwezinye.
Izinto eziphilayo kwakudingeka zivumelane nesimo sezulu. Bakwazi ukuhlala phezu kokuqothulwa okwenzeke esikhathini esedlule. Enye yalezi taxa kwakuyi-angiosperms.
Izimbali nezilwane
Izilwane ezincelisayo ezazitholakala ngaleso sikhathi zazigcinwa zinezici ezifana nalezi ezitholakala namuhla. Phakathi kwazo, ihhashi, inkawu, ukuhlukahluka kwezitshalo nokunye kwezilwane ezincelisayo kugqamile. Ngemuva kokuqothulwa ngasekupheleni kweCretaceous, izinhlobo eziningi zezilwane ezincelisayo zachuma. Lezi zilwane zikwazile ukwehlukahluka, zaba uhlobo oluhlukile emhlabeni.
Enye yezinhlobo ezibaluleke kakhulu zezilwane ezincelisayo kwakuyizilwane zasendle ezavela ngokuhamba kwesikhathi zaba yiHomo sapiens.
Izigaba zePaleogene
Isikhathi se-Paleogene sehlukaniswe izikhathi ezintathu ezinezici ezahlukahlukene ze-geology, i-flora nezilwane nezimo zezulu ezahlukahlukene. Lezi zigaba ezintathu zimi kanje: I-Paleocene, Kulungile y Oligocene.
I-Paleocene
Kungowokuqala isigaba esineminyaka eyizigidi ezingama-65 futhi saqhubeka kwaze kwaba yiminyaka eyizigidi ezingama-56. Kulesi sikhathi, ukuhlangana okuphelele kwezwekazi lasePangea kwenzeke. Wonke amapuleti ama-tectonic ahlukaniswe ekugcineni ahlukaniswa ne-Antarctica ne-Australia. Imiphakathi emincane yezilwane ezincelisayo zasebusuku yayikhona njengezici zombili zokudla okunomsoco kanye nezinambuzane. Lapha sithola amagundane, izinyoni nezilwane ezihuquzelayo ezazizosinda ngalesi sikhathi.
Kulungile
Lesi sigaba sithathe iminyaka eyizigidi ezingama-56 saya eminyakeni eyizigidi ezingama-34. Lapha yonke inkabazwe yasentshonalanga kwakungukukhuphuka kwezintaba ezinkulu ngokushayisana kwamapuleti ama-tectonic. Isimo sezulu besishisa futhi sinomswakama ngalesi sikhathi. Umehluko emazingeni okushisa ubhalwe yi-equator, meridian kanye nezigxobo. Ngokuqondene nezilwane, izilwane zasendulo ezinjenge-marsupials nama-lemurs zavela.
Oligocene
Lesi sigaba sithathe iminyaka eyizigidi ezingama-34 saya eminyakeni eyizigidi ezingama-23. Ngalesi sikhathi i-geology ibigxile ekuvaleni igebe empumalanga engasempumalanga yeTethys Ocean. Konke lokhu kwenzeka ngesikhathi i-Australia ishayisana ne-Indonesia ne-plate yaseNyakatho Melika yaqala ukugqagqana no-Pacific Ocean. Mayelana nesimo sezulu, izinga lokushisa lomhlaba ligcinwe ngendlela eshisayo nenomswakama. Ngokushesha ngemuva kwalokho, lo mkhuba wawushintsha ubheke ekupholiseni umhlaba wonke lapho kufika isikhathi seqhwa. Engxenyeni yezilwane sithola ama-creodonts aye athatha izinyathelo ezibalulekile ekuthuthukisweni kwawo. Izilwane ezincelisayo. Zasungulwa ukuze zibuse konke ukuphila kwasemhlabeni emhlabeni. Esinye sezibonelo ezibaluleke kakhulu ngamakamela amancane nezindlovu zokuqala ezazingenamazinyo. Ngaphezu kwalokho, amabutho akhe ayemfishane kakhulu.
Njengoba ukwazi ukubona, isikhathi sePaleogene sigcwele ukuthuthukiswa kwezimbali nezilwane futhi kuthakazelisa kakhulu ezingeni le-geological. Ekupheleni kwePaleogene, ukuthuthukiswa kwezinkawu kwaqala, okwathi kamuva kwavela kumuntu wamanje. Ngiyethemba ukuthi ngalolu lwazi ungafunda kabanzi mayelana nesikhathi sePaleogene.