Inda muka fito da abin da ya sa mu mutane su ne manyan tambayoyi biyu na kimiyya. Masanin ilimin halittu na Sweden da masanin ilimin halitta Svante Pääbo (Stockholm, 1955) an gane shi a wannan shekara tare da lambar yabo ta Nobel a fannin likitanci saboda gudummawar da ya bayar wajen amsa waɗannan tambayoyin tare da kayan aiki: DNA prehistoric.
A cikin 2010, mai binciken ya tsara jerin kwayoyin halittar Neanderthal, dangin dangi na zamani. Bugu da kari, shi ne ya gano wani hominid da ba a san shi ba, na Denisova. Mun yi nazarin waɗanda aka ba su damar kammala cewa ’yan Adam na zamani suna ɗauke da kwayoyin halitta daga waɗannan tsofaffin jinsuna biyu, waɗanda muka danganta da su bayan ƙaura daga Afirka kimanin shekaru 70.000 da suka wuce. Har yanzu tasirin mu. Misali, ta yadda tsarin garkuwar jikinmu ke daukar cututtuka.
Ayyukan Pääbo, wanda alkalai suka gane a Cibiyar Karolinska a Sweden a matsayin "mai mahimmanci", ya haifar da sabon horo na kimiyya gaba daya: paleogenomics. A cikin 2018 akwai bambanci a gare shi tare da lambar yabo ta Princess of Asturia. Wannan shi ne na farko da lambar yabo ta Nobel ta amince da bincike kan juyin halittar dan Adam, a tarihi ya mayar da hankali kan siffar burbushin halittu, amma masanin ilmin halitta dan kasar Sweden ya hada kwayoyin halitta a matsayin sabuwar hanyar sanin asalinmu. Bayan sanin kyautarsa, Pääbo da kansa ya yarda da mamakinsa: " A gaskiya ban yi tunanin [binciken da na yi] zai ba ni kyautar Nobel ba." Abin mamaki, mahaifinsa, Sune Bergström, ya rigaya ya sami kyautar Nobel don magani a 1982 don gano hormones. Pääbo yana da sunan mahaifiyarsa, masanin kimiyar Estoniya Karin Pääbo.
A farkon aikinsa, mai binciken ya yi sha'awar yiwuwar yin amfani da hanyoyin kwayoyin halitta na zamani don nazarin DNA na Neanderthals. Duk da haka, ba da dade ko ba dade masu matsananciyar fasaha sun fahimci abin da wannan ya ƙunsa, domin bayan dubban shekaru DNA ya ragu sosai, raguwa da gurɓatacce.
Ya fara haɓaka hanyoyin da aka gyara. Ƙoƙarin da ya yi ya biya a cikin 90s, lokacin da Pääbo ya tilasta aiwatar da wani yanki na DNA na mitochondrial daga kashi 40.000 mai shekaru. A karon farko, yi amfani da damar yin amfani da jerin sunayen dangi da batattu. Kwatanta da mutane na zamani da chimpanzees sun nuna cewa Neanderthals sun bambanta ta asali.
Denisovans
An kafa shi a Cibiyar Max Planck a Leipzig, Jamus, Pääbo da tawagarsa sun ci gaba sosai. A cikin 2010 sun sami abin da ba zai yiwu ba ta hanyar buga jerin farko na Neanderthal genome. Binciken kwatancen ya nuna cewa jerin DNA na Neanderthal sun fi kama da jerin mutane na zamani waɗanda suka samo asali daga Turai ko Asiya fiye da na mutanen Afirka. Wannan yana nufin cewa Neanderthals da sapiens sun rayu a lokacin millenni na rayuwa tare a cikin uwa nahiyar. A cikin mutanen zamani na zuriyar Turai ko Asiya, kusan 1-4% na kwayoyin halittar Neanderthal ne.
A shekara ta 2008, an gano wani guntun dutse mai yatsa mai shekaru 40.000 a cikin Denisova Basin da ke kudancin Siberiya. Kashin ya ƙunshi DNA na musamman da aka adana, wanda ƙungiyar Pääbo ta tsara. Sakamakon ya haifar da jin dadi: sun kasance hominid wanda ba a sani ba a baya, wanda aka ba da lambar Denisovan. Kwatanta da jeri daga mutane na zamani daga sassa daban-daban na duniya ya nuna cewa duka nau'ikan suma sun haɗu. Ana ganin wannan dangantakar da farko a cikin yawan jama'a daga Melanesia da sauran sassan kudu maso gabashin Asiya, tare da mutanen da ke da 6% Denisovan DNA.
"Neman abin da ba zai yiwu ba"
Godiya ga binciken Svante Pääbo, yanzu an fahimci cewa jerin halittun archaic daga ɓatattun danginmu suna rinjayar ilimin halittar ɗan adam na zamani. Misalin wannan shine nau'in Denisovan na kwayar halittar EPAS1, wanda aka dogara da shi don fa'idar rayuwa a tsayi mai tsayi kuma ya zama ruwan dare tsakanin 'yan Tibet na zamani. Sauran misalan kwayoyin halittarsa sune Neanderthals waɗanda ke yin tasiri ga sabon martani na rigakafi daga nau'ikan cututtuka daban-daban, gami da Covid-19.
Juan Luis Arsuaga, babban darektan rukunin yanar gizo a cikin Saliyo de Atapuerca (Burgos), ya haɗu a lokuta da yawa tare da masanin ilimin halittar Sweden. "Sun ba da kyautar ga aboki. A matakin sirri, aiki tare da Nobel yana da ban sha'awa. Bugu da ƙari, ya buɗe sabon layin bincike. Ya cancanci hakan saboda shi majagaba ne, mai hangen nesa, "ya gaya wa wannan jarida, yayin da yake tuna cewa DNA mafi tsufa na Sima de los Huesos, a Atapuerca.
Masanin ilimin halitta Carles Lalueza Fox, sabon darektan Gidan Tarihi na Kimiyyar Halitta na Barcelona, yana da ra'ayi ɗaya kuma yana aiki tare da Pääbo a cikin nazarin gidajen cin abinci na Neanderthal a wurin Asturian na El Sidron. "Shi majagaba ne, yana neman abin da ba zai yiwu ba," in ji shi. "Na gode da yadda ya iya yin aiki, mun san cewa juyin halittar ɗan adam ya fi rikitarwa fiye da yadda muke zato, tare da giciye na zuriya daban-daban, a lokuta daban-daban da sassan duniya, suna samar da nau'in hanyar sadarwa," in ji shi. fita.
Binciken Pääbo yana taimaka mana mu ji ko wanene mu, abin da ya bambanta mu da sauran nau'in ɗan adam da kuma abin da ya sa namu kaɗai ne a fuskar duniya. Neanderthals, kamar sapiens, suna zaune a rukuni, suna da manyan kwakwalwa, suna amfani da kayan aiki, sun binne matattun su, suna dafa, kuma suna ado jikinsu.
Har ma sun ƙirƙira fasahar kogo, kamar yadda zane-zane na aƙalla shekaru 64.000 da suka gabata suka nuna a cikin kogon Spain uku: La Pasiega a Cantabria, Maltravieso a Cáceres da Ardales a Malaga. Sun kasance kama da mu amma suna da bambance-bambancen kwayoyin halitta wanda Pääbo ya kawo haske kuma wanda zai iya bayyana dalilin da yasa suka ɓace kuma har yanzu muna nan.
