Ngaphakathi Ixesha leCenozoic sinayo Ixesha Paleogene. Lulwahlulo lwexesha elidibanisa iminyaka engama-66 ezigidi kwaye yaphela malunga ne-23 yezigidi zeminyaka eyadlulayo. Ngeli xesha sinokudaleka okukhulu kwezilwanyana ezincancisayo ngaphandle kwento yokuba kuye kwafuneka ukuba zivele kwindidi ezinobungakanani obuncinci. Inkqubo ye- Izilwanyana zePaleogene phawula ngaphambi nasemva, ngakumbi kwizilwanyana ezanyisayo.
Ke ngoko, siza kunikezela eli nqaku ukukuxelela ngazo zonke iimpawu kunye nokuvela kwezilwanyana zasePaleogene.
Ixesha Paleogene
Eli xesha yayiyimvelaphi yeefom zakudala zobomi bamva nje. Kufuneka sikhumbule ukuba ekuqaleni kweli xesha lokuma komhlaba bekukho ukuphela okuphelelweyo okuhambelana nedinosaurs ixesha elimdaka. Kwi-geology yeli xesha siyabona ukuba amacwecwe e-Australia kunye ne-India ahamba kwicala elingasempuma-mpuma ngenxa yokuhamba kwelizwekazi. Kuqikelelwa ukuba isantya sokuhamba kwezi Amacwecwe etektoni ayemalunga neesentimitha ezi-6 ngonyaka. Okwangoku eli zinga liphantsi kakhulu.
Kufuneka kwakhona sithathele ingqalelo ukuba izilwanyana zePaleogene zichaphazele utshintsho lwemozulu kwinqanaba lehlabathi. Kwakukho utshintsho olukhulu kwimozulu njengokupholisa ngokubanzi kuyo yonke imimandla esecaleni. Ngenxa yokwehla kwawo onke amaqondo obushushu ehlabathi, kuye kwakho ukuvumela iplanethi iphole. Njengoko ixesha lePaleogene liqhubeka, amaqondo obushushu eplanethi anyuke kwakhona. Kwaye kukuba ukwanda kwamaqondo obushushu kuncede ukuba kubekho imozulu yetropiki kwiindawo ezininzi. Njengoko sisazi, imozulu yetropiki ibonakaliswa ikakhulu yi ubuninzi bamaqondo obushushu aphezulu, ukufuma okuphezulu kunye nemvula elungileyo. Konke oku kukhokelela kuphuhliso lwezilwanyana zePaleogene.
Izinto ezininzi eziphilayo ziye zaqhelana nemozulu kwaye zikwazile ukwenza oko ngaphandle kokuphela okwenzeke kwixesha elidlulileyo. Enye yeetaxa enokuphuhliswa zizityalo ze-angiosperm.
Izilwanyana zePaleogene
Ixesha le-Paleogene lahlulwe laba ngamathuba amathathu: i Paleocene, i Ilungile kunye Oligocene. Kweli xesha ngalinye sifumana ukukhula okwahlukileyo kwezilwanyana zePaleogene. Makhe sihlalutye zeziphi iinkcukacha.
Paleocene
Ngexesha le-Paleocene safumana inani elikhulu lezilwanyana ekwakufuneka ziphila ekuphelisweni kobunzima beCretaceous engasekhoyo. Ngombulelo kwesi siganeko sokuphela kobunzima, izilwanyana zikwazile ukuphuhlisa izimo zengqondo ezahlukeneyo zokuziqhelanisa neemeko ezintsha. Ukuphela kwalo kulinike ithuba lokwahluka-hlula nokwanda kwiintlobo ezithile zezityalo nezilwanyana. Baye balisebenzisa ngakumbi eli thuba lokuba iidinosaurs sele zilapho. Kwaye ngaba zizilwanyana zithathwa njengezona zilwanyana zibaluleke kakhulu kwihlabathi lonke. Zonke izilwanyana kwafuneka zikhuphisane ngezixhobo zendalo kunye needinosaurs.
Phakathi kwezilwanyana zePaleogene ezibalaseleyo kwixesha lePaleocene sinezirhubuluzi. Babeliqela lezilwanyana ezazisinda ekutshatyalalisweni kakuhle kwaye bababalwe ngenxa yemozulu yeli xesha. Phakathi kwezona zinambuzane zininzi sifumana iicampusosaurs ezihlala ikakhulu kwiindawo ezinamanzi. Iinyoka kunye neefudo zaselwandle nazo zibe nophuhliso olukhulu.
Ngokubhekisele kwiintaka, zandisa ukubonga ngokunyuka kwamaqondo obushushu kwimimandla yetropiki. Iintaka ezoyikekayo zazisaziwa ngelo xesha. Zazinkulu kodwa zingenakho ukubhabha. Imikhwa yezi ntlobo zazidla kwaye yathathelwa ingqalelo njengamarhamncwa awoyikekayo kwizilwanyana ezininzi. Ezinye iintlobo zeentaka ezifumene ukukhula okukhulu ngexesha lezilwanyana zasePaleogene Iilwandle, amahobe, izikhova kunye namadada.
Izilwanyana zaselwandle zikwaphuhlise kakhulu malunga neentlanzi. Yenze ukhuphiswano olukhulu ebaleni lolwandle kunye nookrebe basasazeka baba zizilwanyana ezilawulayo ezintsha. Kwintsimi yezilwanyana ezanyisayo, enye yezilwanyana esele ziphuculwe kakhulu ngexesha lezilwanyana zePaleogene, sifumana iingqameko, iimonotremes kunye neemarsupial. Sikwafumana iqela leempuku, iinyamakazi, iiemurs, phakathi kwabanye.
Ilungile
Kwixesha le-Miocene, izilwanyana ze-Paleogene zaphuhliswa ikakhulu kwiqela lezilwanyana ezanyisayo kunye neentaka. Izilwanyana ezingenamqolo zikwazile ukuphuhlisa kunye nokwahluka kancinci kulwandle. Uninzi lwee-mollusks, i-gastropods, i-bivalves, i-cnidarians echinoderms inokukhula ngexesha. Iqela leembovane lelona qela liphucukileyo lezilwanyana ngokwee-invertebrates.
Iintaka zaziziintlobo ezathi zabakho ngenxa yemeko-bume entle. Ezona zininzi zaziziintlobo ezaziwayo Njengo Phorusrhacidae, Gastornis kunye noonombombiya. Kwintsimi yezirhubuluzi kunye nezilwanyana ezanyisayo ezikhule kakuhle, safumana izilwanyana ezinokufikelela kwiimitha ezili-10 ubude. Phakathi kwezi zilwanyana sinezinto ezingafakwanga, ii-cetaceans kunye nee-Ambulocytids. Isilwanyana ngasinye sasineempawu ezikhethekileyo ezazisinceda siziqhelanise nemo engqongileyo ngelo xesha.
Oligocene
Inxalenye yokugqibela yezilwanyana zasePaleogene ibhekisa kwizilwanyana zaseOligocene. Ibonakaliswa ngokuba namaqela amaninzi ezilwanyana ezahlukileyo kwaye zichuma nangona iimeko zemozulu zazifunyenwe. Apha ukuvela kwezinto ezanyisayo kubonakala. Inani elikhulu leentlobo zezilwanyana ezanyisayo zavela, phakathi kwazo sineempuku, ii-canids, ii-primates kunye neecetaceans.
Iimpuku zazinempawu eziphambili zokuba ne-incisors ebukhali kakhulu enokusetyenziswa okuninzi. Ukusetyenziswa kwayo ikakhulu leyo yokuluma amarhamncwa okanye ukuhlafuna iinkuni. I-Primates liqela eliphuhlileyo lezilwanyana ezincancisayo kwaye zibonakaliswe ngokuba neenzwane ezintlanu emilenzeni yazo. Phakathi kwezibonelelo zokuzivelela kwezi zilwanyana ngaphezulu kwezinye izilwanyana ezanyisayo kukuba zinobhontsi abachasayo. Ukongeza, baneenyawo zokutyala ezivumela ukuba yonke inyawo ixhaswe ukuze ihambe ngokukuko.
Ii-Canids zeli qela leengcuka nezinja. Olona phawu lwabo luphawu lokuba nomzimba ophakathi kwaye bahamba ngeengcebiso zeminwe. Banokutya okutyayo kwaye bahlala befumaneka kwikhonkco lamarhamncwa kwityathanga lokutya.
Okokugqibela, iicetaceans yayiliqela lezilwanyana ezanyisayo ezathi zakhula kancinci ngexesha lezilwanyana zePaleogene. Zezona zilwanyana eziye zaqhelana nobomi baselwandle nangona ziqhubeka nokuphefumla kwemiphunga.
Ndiyathemba ukuba ngale ngcaciso ungafunda ngakumbi malunga nezilwanyana zePaleogene.