The characteristics of the genus Homo appear between 3 and 2 mya, and it is assumed they are caused by climatic changes and the consequences are best seen in the eastern part of the African continent thorugh mammal fossil finds. A place where fossils attributed to Homo habilis, the oldest member of the genus, can be found is located east of the Great Rift Valley. By 1,9mya traces of two other species, Homo rudolfensis and Homo erectus can be found, and 100,000 later, traces of Homo erectus were found outside of Africa, across Euroasia and south-eastern parts of the Asian cotinent. Further development of the genus Homo can be traced through fossil finds from Spain with more developed morphology of Homo antecessor, but also with development of Homo heidlebergensis, probably in Africa. Although the development of Homo neanderthalensis and Homo sapiens is still uncelar, and has many aspects, which include fossil finds from Denisova cave in Siberia, the traces of neanderthal morphology can be seen around half a milion years ago, and traces of fully modern morphology 200,000 years later. Two modern species have coexisted for a long period of time and have left undisputed traces of modern behavior, untill only Homo sapiens remained.