Namuhla sizokhuluma nge Izilwane ze-Ediacara. Kuyisethi yezinto eziphilayo ezimele zonke izinhlobo zezinto eziphilayo ezazihlala eMhlabeni ngesikhathi se-geological esaziwa nge-Ediacara. Lesi sikhathi senzeka eminyakeni eyizigidi ezingama-600 edlule. Kucatshangwa ukuthi le fauna ingahle ihlotshaniswe nokwanda okwenzeka ngaleso sikhathi emazingeni omhlaba oksijini akhona emoyeni.
Kulokhu okuthunyelwe sizohlola kahle izilwane zase-Ediacara ukuthola zonke izimfihlo zazo.
Origen
Ososayensi bacabanga ukuthi izilwane zase-Ediacaran zaqala ekwandeni komoya-mpilo womkhathi owenzeka eminyakeni eyizigidi ezingama-600 edlule. Leli qiniso lithanda ukuthuthukiswa kwama-metazoans ahlukahlukene akudala anezici ezifanayo: umzimba onokuthungwa okuthambe kakhulu nezimo ezahlukahlukene. Lezi zilwane zitholakale endaweni ye-paleontological etholakala ezintabeni zase-Ediacara, e-Australia.
Amarekhodi ezinsalela zalezi zilwane agcinwa ezifundeni ezahlukahlukene zomhlaba. Le fauna imele ukuthuthuka okubalulekile ezintweni eziphilayo ezinamaseli amaningi ngaphambi kokuqhuma kweCambrian. Ingenye yezindlela zokuqala zokuphila ezazidinga umoya-mpilo emkhathini ukuze ikhule. Ngaphezu kwalokho, ososayensi bacabanga ukuthi kuyisandulela sezinto eziphilayo ezinamathambo.
Ngaphandle kokuthi umhlaba wawakhiwe iminyaka eyizigidi eziyizinkulungwane ezingama-4550, bekungekho kuze kube yiProterozoic lapho bekukhona umkhathi noma ukushintshela esimweni esinokuqukethwe okuphezulu komoya-mpilo. Phambilini, bekukhona izinto eziphilayo ze-methanogenic kuphela, ngoba ukugxila kwe-methane esemkhathini bekuphakeme kakhulu futhi lezi zinto ziphila ngokuvumelana nezimo ze-anaerobic.
Isigaba sokugcina sesikhathi seNeoproterozoic saziwa njengenkathi ye-Ediacaran. Ekuqaleni kwalesi sikhathi sokuma komhlaba kulapho izidalwa ezindala ezinamaseli amaningi zaqala ukukhula. Lezi zidalwa zisekhona nanamuhla futhi yizona zakudala kakhulu esizaziyo. Lezi yizipanji zokuqala kanye nama-anemone. Lesi sikhathi sokuma komhlaba saqala eminyakeni eyizigidi ezingama-635 eyedlule saphela eminyakeni eyizigidi ezingama-542 edlule.
Azikho izinsalela ngaphambi kwezilwane zase-Ediacara
Enye yezincazelo ezinganikezwa ngeqiniso lokuthi azikho izinsalela zanoma yiziphi izilwane ezikhona ngaphambi kwalesi sikhathi se-geological ukuthi izidalwa eziphilayo zangaphambilini bezingenayo i-collagen. I-Collagen yiprotheni enemicu esiza ukuqinisa umzimba wesilwane futhi iyivumele ukuthi igcinwe ngokuhamba kwesikhathi.
Le nhlanganisela ephilayo kwenzeka kuphela lapho izinga le-oxygen esemkhathini likhulu kune-3%. Ngakho-ke, i-collagen ayizange yakhiwe ekuqaleni kwesimo se-anaerobic.
Kunemibono ethile ngokufana kwezilwane zase-Ediacaran kanye nezindlela zamanje zezilwane. Enye inkolelo-mbono ukuthi eziningi zalezi zilwane zingokhokho ngqo bezinhlobo esizaziyo namuhla. Ngakolunye uhlangothi, kunokunye ukuqagela kokuthi izilwane ze-Ediacara zinokuziphendukela kwemvelo okuhluke ngokuphelele futhi kukodwa. Lokhu kusho ukuthi ayinakho ukuxhumana nezidalwa eziphilayo esizaziyo namuhla. Lesi yisizathu esenza ukuthi ihlukaniswe nge-phylum ehlukile eyaziwa njenge-extinct phylum Vendozoa.
Uma kwenziwa ukuhlolwa kwezinsalela ezitholakele, siyabona ukuthi ezinye izinhlobo zezilwane zase-Ediacara ziyefana nalezo ezazihlala eCambrian. Leli qiniso lisho ukuthi, ngandlela thile, zingahlobana nezinto eziphilayo zamanje. Esinye sezibonelo ezisetshenziswe kakhulu ngesikaKimbelerra Cuadrata. Kuyinhlobo ebiphila esikhathini se-Ediacaran futhi ifana kakhulu nezimbungulu zamanje.
Futhi, yize kunezindlela ezithile ezibonakala ziphikisana ngokuphelele, ukuba khona kwezilwane zase-Ediacara kungaba yincazelo yokuvela kwezinhlobo eziningi zesimanje esinazo namuhla.
Izici eziyinhloko
Izinsalela ezitholakale kumadiphozithi e-paleontological zakhiwa ngokumboza ulwandle ngodaka nesihlabathi esihle. Yile ndlela okwenziwa ngayo ukudangala okuthile emizimbeni engaphansi kwesihlabathi. Njengoba inamaphesenti aphezulu wamanzi, yehle ngobukhulu, okunika izinsalela zamathambo ukubukeka okubushelelezi futhi okuyindilinga.
Lezi zilwane kucatshangwa ukuthi zazihlala eduze kwezidalwa ezitholakala eshalofini elingajulile lezwekazi. Lokhu kwenze ukuthi bakwazi nokuhlala ekujuleni kwamamaki ezwekazi ayekhona ngalesi sikhathi.
De amarekhodi ezinsalela ze-Ediacaran athola izinto eziphilayo ezazinomzimba othambile. Lokhu kucatshangwa ukuthi kunjalo, ngoba kukhona ubujamo bediski obakhiwe yizakhiwo ezinamathele. Ungabona futhi ama-radials angaphakathi noma inhlanganisela yakho kokubili.
Esinye isici sezinsalela ukuthi ezinye zitholwe zinenqwaba engajwayelekile neyama-amorphous ezingaba ezakhiweni zakudala zama-sporophytes.
Ukuqothulwa kwezilwane zase-Ediacara
Kuthiwa lezi zilwane zaphela nya ekupheleni kwePrecambrian. Imbangela kungenzeka ngenxa yokudla okunamandla kwalezi zilwane zasendulo kanye nokwehluka okwakukhona ezingeni lolwandle. Ukuklabisa ngokweqile kwabangela ukuqothulwa kwezitshalo eziningi ezazisebenza njengesondlo sezilwane.
Kodwa-ke, yize kunenkolelo yakudala, kuyaziwa kusuka ocwaningweni olusha lwakamuva ukuthi ezinye izinhlobo ze-Ediacaran zaziphila ngesikhathi seCambrian.
Ezinye zezizathu zokuthi kungani zonke izinhlobo zezinto eziphilayo zanyamalala yilezi:
- Ama-glaciations: Yizikhathi ezibandayo zamakhaza ezidala imigoqo yokuthi izinto eziphilayo zikhule futhi zikhule.
- Ukudla: Zonke izinto eziphilayo esikhathini seCambrian zaziyizilwane ezidla amagciwane. Uma lesi sidlo saqala ngesikhathi sokuncipha kwezilwane zase-Ediacaran, mhlawumbe yiyona imbangela enkulu yokuqothulwa kwezinhlobo eziningi.
- Izinguquko zemvelo. Izinguquko ezinkulu zokwakheka komhlaba, ezemvelo nezesimo sezulu ezenzeke ekupheleni kwePrecambrian nasekuqaleni kweCambrian zenze eziningi zezinhlobo zingakwazi ukuzivumelanisa nezimo ezintsha zemvelo.
Ngiyethemba ukuthi ngalolu lwazi ungafunda kabanzi ngezilwane zase-Ediacara.