Duba wurin da ke ƙasa sannan ka amsa tambayar daga baya a cikin harshe ɗaya kamar yadda wurin yake:  Passage: Wallace, bin aikin da de Candolle, Humboldt da Darwin suka yi a baya, sun ba da babbar gudummawa ga ilimin dabbobi. Saboda sha'awarsa a cikin hasashen canzawa, ya ba da kulawa ta musamman ga rarraba yanayin yanayin nau'ikan da ke da alaƙa a lokacin aikinsa na farko a Kudancin Amurka sannan kuma a cikin tsibirin Malay. Duk da yake a cikin tsibirin ya gano layin Wallace, wanda ke gudana ta tsibirin Spice wanda ke raba fauna na tsibirin tsakanin yankin Asiya da yankin New Guinea / Australia. Babban tambayarsa, game da dalilin da ya sa fauna na tsibiran da ke da irin wannan yanayi ya bambanta, za a iya amsa shi ne kawai ta hanyar la'akari da asalinsu. A shekara ta 1876 ya rubuta The Geographic Distribution of Animals, wanda shine aikin da aka saba amfani da shi fiye da rabin karni, da kuma ci gaba, Island Life, a 1880 wanda ya mayar da hankali kan tsibirin biogeography. Ya fadada tsarin yankuna shida da Philip Sclater ya kirkira don bayyana rarraba yanayin tsuntsaye ga dabbobi iri daban-daban. Hanyar sa ta tattara bayanai kan kungiyoyin dabbobi a yankuna na kasa ya nuna rashin ci gaba; kuma jin dadinsa na juyin halitta ya ba shi damar bayar da shawarwari masu ma'ana, wanda ba a yi ba a baya. Nazarin kimiyya na gado ya karu da sauri a bayan Darwin's Origin of Species tare da aikin Francis Galton da masu nazarin halittu. Asalin ilimin kwayoyin halitta yawanci ana bin diddigin aikin 1866 na ɗan sufi Gregor Mendel, wanda daga baya za a yaba da dokokin gado. Amma, ba a san muhimmancin aikinsa ba sai bayan shekara 35. A halin yanzu, an yi muhawara da bincike sosai game da ra'ayoyi da yawa game da gado (wanda ya dogara da pangenesis, orthogenesis, ko wasu hanyoyin). Embryology da kuma muhalli sun zama manyan fannoni na ilimin halitta, musamman kamar yadda aka danganta da juyin halitta da kuma yaduwa a cikin aikin Ernst Haeckel. Yawancin aikin karni na 19 akan gado, duk da haka, ba a cikin tarihin halitta ba, amma na ilimin lissafi na gwaji.  Tambaya: Wanene ke da alhakin ɓangaren ilimin halittar jiki da ilimin halittu ya zama manyan fannonin ilimin halitta?
Ernst Haeckel