Ishusho ya Charles Darwin, Umwongereza wanditse igitabo “L’origine des espèces” na “L’origine de l’homme”
Rero, niba umurizo ufite ihuriro no guhinduka kw’abantu n’ibisabantu kandi waragize ingaruka ku ngendo (demarche) zabyo, ikibazo kibazwa ni icyaje mbere, umurizo cyangwa amaguru?
Xia ati: “Ni nk’ikibazo cy’igi n’inkoko. Nk’uko mwabyibaza, ntabwo ari ikibazo byoroshye gusubiza.”
Muri macye, ntabwo bishoboka kumenya neza ibyabanje kugira ngo abasokuru bacu bahagarare ku maguru, niba byaratewe n’uko nta mirizo bari bafite.
Cyangwa se niba tudafite imirizo kuko tugenda duhagaze kandi bikaba byoroshye guhagarara twemye ku maguru yacu.
AHAVUYE ISANAMU, GETTY IMAGES
Insiguro y’isanamu, Iyo witegereje cyane, ubona ibintu byinshi ibisabantu bimwe bihuriyeho natwe abantu
Xia ati: “Byasaba imashini yasubiza inyuma ibihe kugira ngo ibyo byose bimenyekane, tukareba ibyabanje. Ariko kuko ntayo dufite, icyo navuga ni uko tutabizi, impaka zigashirira aho. Ariko umuntu akaza kwibaza ati ‘kuki tuvuga ibyo byose’.
“Igisubizo nyacyo ni uko iby’amaguru n’umurizo bigibwaho impaka icya rimwe. Muri macye ntitwavuga kwihinduranya (evolution) ngo ntidukomoze ku murizo no ku maguru abiri, tutitaye ku cyaje mbere.”
Igisubizo kiri mu guhererekanya ibitugize
Kuva yababara akagufa ko ku ruti rw’umugongo (coccyx) ari mu modoka, hashize imyaka ibiri, Xia ntiyigeze areka gutekereza ku ngingo y’imirizo n’abantu.
Coccyx niko kagufa ka nyuma ko hasi ku ruti rw’umugongo, kagizwe n’utugufa tune dufatanye kandi kerekana ishusho y’icyahoze ari umurizo mu myaka miliyoni nyinshi ishize.
Iyo urebye amashusho y’umwana ukiri gutangira kwirema (embryon) mu nda ya nyina, ubona umurizo, uza kugenda nyuma y’ibyumweru bicye mu ikorwa ry’uruti rw’umugongo.
Iyo coccyx, niyo twicarira, iri ahantu neza neza umurizo uba uri ku zindi nyamaswa.
Itai Yanai umushakashatsi mu buvuzi wo muri kaminuza ya New York avuga ko mu myaka 100 ishize science yageze kuri byinshi mu kwiga ibijyanye no guhererekanya ibitugize kw’abantu (génétique).
Ati: “Twibaza ibi bibazo byose kuko abantu bakunda science kandi ari yo bajyaho mu gushaka ibisubizo ku bibazo runaka.”
Kwihinduranya kwabonywe na Xia Bo mu bushakashatsi bwe ku mbeba kwerekana utunyangingo tubarirwa mu magana tuzwi nka TBXT, ako ni agace kagize ADN kandi usanga ari kamwe ku bantu no ku bisabantu.
Mu gusuzuma ihuriro hagati yo kwihinduranya n’umurizo, Xia yahinduye utunyangingo tumwe na tumwe duhererekanywa ku mbeba akoresheje uko kwihinduranya.
Eureka! Xia na bagenzi be bavumbuye ko umurizo w’imbeba utongeye kumera nk’uko byagendaga mbere.
AHAVUYE ISANAMU, GETTY IMAGES
Insiguro y’isanamu, Hari utunyangingo twinshi dutuma inyamaswa zimera umurizo
Ariko ubwo buvumbuzi ni ubwa mbere mu ruhererekane ruzatuma tumenya neza ibyo kwihinduranya kwabaye ku basokuru bacu.
Abahanga muri science bavuga ko hari utunyangingo turenga 30 dutuma inyamaswa zimera umurizo, kandi abashakashatsi b’i New York bo bavuga kamwe.
Nk’uko Xia abivuga, abantu bose bafite amagufa y’umurizo kandi asa, ariko kuri za mbeba zakoreweho ubushakashatsi imirizo yari ifite uburebure butandukanye cyangwa se nta yo na mba.
Umwanzuro wa Xia ni uko habayeho kwihinduranya gutandukanye, aho kuba kumwe, kwahinduye utunyangingo duhererekanywa kuri za hominines mu myaka igera kuri miliyoni 25 ishize maze bigahindura abantu uko tumeze ubu.
Ati: “Birashoboka ko ari ukwihinduranya gukomeye, ariko ntitwibaza ko ari ko gusa kwabiteye.”
AHAVUYE ISANAMU, GETTY IMAGES
Insiguro y’isanamu, Kwihinduranya kwatumye abantu batakaza imirizo kwanahinduye ingendo yabo
Xia na Yanai bavuga ko kwihinduranya gushobora kugira ingaruka mbi, harimo kurwara cyangwa no gupfa.
Ariko kandi kwihinduranya kuzana ibyiza aho gushobora kwakirwa neza n’abo kubayeho maze kugahererekanywa ibiragano ku bindi.
Icyo Xia asobanura ni uko gutakaza imirizo kwazaniye ba hominidis (bwa bwoko duhuriramo n’ibisabantu bidafite imirizo) ibyiza kandi by’ingenzi bisobanura impamvu kwamaze igihe kirekire.
Ati: “Cyane cyane uko abantu bagenda cyangwa uko dukoresha intoki mu gukora ibintu bitandukanye.”
Ariko ibyo ngo ntabwo bisobanuye ko gutakaza imirizo byatuzaniye ibyiza gusa.
Xia n’itsinda rye babonye ko imbeba bakoresheje mu bushakashatsi zagize imiterere mibi ku ruti rw’umugongo isa cyane n’indwara y’umwobo ku ruti rw’umugongo ifata umwana umwe w’umuntu ku bana 1,000 bavutse.
Ubwo busembwa buva ku kitwa spina bifida, kibaho iyo uruti rw’umugongo ruri kwikora ku mwana utaravuka rutifunze neza.
Xia ati: “Sinavuga rero ko kwihinduranya ari byiza cyangwa bibi. Ni ikintu kibaho gutyo gusa.”
AHAVUYE ISANAMU, GETTY IMAGES
Insiguro y’isanamu,Abahanga muri science bamaze kumenya uko twatakaje imirizo ariko ntabwo baramenya neza impamvu
Kuri M.Yanai imirimo y’abashakashatsi izafasha kumva ibintu byabaye mu mateka ya cyera cyane y’abasukuru bacu.
Ati: “Nibaza ko ibyo Bo (Xia) yagezeho bizafasha umuryango w’abahanga muri science kurushaho kugera ku bindi.”