Ingcaphuno evela ku-movie «Umgwaqo»
Kungenzeka sike sakhuluma ngegama elithi "ubusika benyukliya" ngesikhathi esithile, njengomphumela wesigameko esithile esibucayi noma isimo sezulu. Ngokwesibonelo, okulindeleke ukuthi kwenzeke uma ngabe I-Campi Flegrei supervolcano. Lokhu kuphola okungazelelwe okuzokwehlelwa yiplanethi kuzoba nokufana okukhulu nobusika benyukliya. Kepha kuyini ngempela?
Lolu hlobo lobusika ngumqondo oqukethe isikhathi sezulu esivele sizohlala ngemuva kwempi yenuzi. Imiphumela ingaba mikhulu kakhulu lapho kungavela into ebizwa nge- "bottleneck". Cishe, kungukunyamalala okusheshayo kwezingxenye eziphelele noma eziyingxenye yohlobo oluthile noma inani labantu. Lo mcimbi uholela kulokho okubizwa nge- "genetic drift" nakho, okuphikisana nakho, okukhuthaza ukuvela kohlobo. Kungumphumela wokuphendula ngamaketanga okungekho zilwane ezizosindiswa kuwo, futhi ngisho nabantu okudingeke badlule kukho emlandweni wabo.
Imiphumela yobusika benyukliya
Ngamafuphi, ubusika benyukliya buyisimo sezulu esivela ekusetshenzisweni ngokungakhethi kwamabhomu enuzi. Lokho kuphola komhlaba kuzovela okukhulu amafu othuli abengakhuphukela emkhathini. Le ndawo, ebangeni eliphakathi kwamakhilomitha ayishumi kuya kwangama-10 ukuphakama, ibingagcwalisa okokusebenza kungavimbela ukudlula kwelanga. Hhayi kuphela empini enamabhomu e-athomu, kulandela ukuthi i-supervolcano nayo izoba nomphumela ofanayo ngenxa yamakholomu amakhulu wezinto ezikhishwe phezulu.
Ngokungafani nobusika obujwayelekile esingabazi, lokhu kungadala ukuncipha kokungena kwelanga. Ezidalweni eziphilayo ezenza i-photosynthesis, kungasho ukufa okuphelele noma okuyingxenye kohlobo. Enye into ebingalindelekile ukuthi, yize kwaziwa ukuthi imiphumela yayo ingaba mibi, lelo fu lothuli angahlala ezulwini izinyanga eziningi. Mingaki eminye, umonakalo omkhulu ezimalini zemvelo. Kusukela ekufeni kwezitshalo, kuzoza ngemuva kwayo, ukuqhuma kokuqothulwa kulandela uchungechunge lokudla. Ngemuva kwezitshalo, ama-herbivores ayeza, kuthi emva kwawo kube nezidliwayo. Kungenzeka ukuthi kuye ngobukhulu nendawo, umoya ongachazeki ngokwawo wabangela izilwane ukuba zife ngokushesha ezifundeni. Ngokusho kweminye imibono, lo mkhuba ubuye wasetshenziswa njengencazelo yokuqothulwa kwama-dinosaurs yi-meteorite eyadala imiphumela efanayo.
Kwenzeka kanjani ukuba ibhodlela?
"I-bottleneck" igama elisetshenziswe ku-biology ukubhekisa ezikhathini ezedlule lapho, kusuka ochungechungeni lwezehlakalo, inani lezinto eziphilayo lehliswe kakhulu ngesibalo futhi lafinyelela nasekuqothulweni. Izizathu zithande ukuhlale zihambisana nezinhlekelele ezinkulu. Ngakho-ke lapho ngaphambi kokuba sibe nenani elikhulu labantu elinokuhlukahluka okukhulu kofuzo, manje selincane futhi lishintshashintsha kancane.
Konke lokhu kuholela ekubanjweni kokuthi ukwehluka okuncane kuholele kufayela le- ukuqhuma kofuzo, ngenxa yokucaca nokuziphendukela kwemvelo okuguqukayo. Esikhathini ngasinye sezikhathi ezirekhodiwe, kube njalo. Abasinda kule nhlekelele, njengobusika benyukliya, basheshisa ukukhula kwabo kofuzo nokuziphendukela kwemvelo, ngaleyo ndlela bakhiqize izinhlobo ezintsha zezinhlobo. Iningi (noma eliqine kakhulu) izici zofuzo zivame ukusimamisa futhi ziqhubeke, kuthi lezo ezibuthakathaka noma ezincanyana ziphele.
Abantu bakuthola nini?
Eminyakeni engama-75.000 eyedlule. Yaziwa njengenhlekelele yaseToba, le supervolcano etholakale e-Indonesia iqhume. Njengamanje iyichibi ngenxa yomgodi omkhulu. Kulinganiselwa ukuthi izinhlobo zabantu zehliselwa kubantu abayizinkulungwane ezimbalwa. Ngaphezu kwalokho, ukwehla okuguquguqukayo kwezinye izinhlobo kuhlangana ngesikhathi esifanayo.
Yize sikhulume ngezintaba-mlilo, ngenxa yobudlelwano bazo nobusika benyukliya, izingqinamba zihluke kakhulu. Lokho wukuthi, abakwazanga ukusukela emiphumeleni yesimo sezulu kuphela, kepha ezinhluphekweni noma emashayabhuqe. Isibonelo, ubhadane olumnyama olwaluphila eYurophu Ephakathi. Noma ngaphezulu, njengokuqhuma, indlala nezifo eziningi njengoba kwenzeka e-Iceland ngokuqhuma kweLake ngo-1783.