of knowledge. Instead, the view now supported by a preponderance of evidence is that it occurred by actual migration out of the region, coupled with subsequent interbreeding with indigenous local populations whom the migrants came in contact with. The studies show also that not all present day Europeans share strong genetic affinities to the Neolithic and Bronze Age inhabitants of the Fertile Crescent; the closest ties to the Fertile Crescent rest with Southern Europeans. The same study further demonstrates all present-day Europeans to be closely related. Languages Linguistically, the Fertile Crescent was a region of great diversity. Historically, Semitic languages generally prevailed in the modern regions of Iraq, Syria, Jordan, Lebanon, Israel, Palestine, Sinai and the fringes of southeast Turkey and northwest Iran, as well as the Sumerian (a language isolate) in Iraq, whilst in the mountainous areas to the east and north a number of generally unrelated language isolates were found, including; Elamite, Gutian and Kassite in Iran, and Hattic, Kaskian and Hurro-Urartian in Turkey. The precise affiliation of these, and their date of arrival, remain topics of scholarly discussion. However, given lack of textual evidence for the earliest era of prehistory, this debate is unlikely to be resolved in the near future. The evidence that does exist suggests that, by the third millennium BCE and into the second, several language groups already existed in the region. These included: Proto-Euphratean language: a non-Semitic language previously hypothesized to be the substratum language of the people that introduced farming into Southern Iraq in the Early Ubaid period. (5300–4700 BCE) The linguistic consensus today is that multiple unknown substrata contributed to the formation of the artifacts in Sumerian names that motivated the Proto-Euphratean substrate hypothesis, including fossilized archaic elements from earlier stages of Sumerian itself. Another theory proposes that the pre-writing substrate was an early Indo-European language tentatively called Euphratic. Sumerian: a non-Semitic language isolate that displays a Sprachbund-type relationship with neighbouring Semitic Akkadian Elamite language: a non-Semitic language isolate Semitic languages: Akkadian (aka Assyrian and Babylonian), Eblaite, Amorite, Aramaic, Ugaritic, Canaanite languages (including Hebrew, Moabite, Edomite, Phoenician/Carthaginian) Hattic: a language isolate, spoken originally in central Anatolia Indo-European languages: generally believed to be later intrusive languages arriving after 2000 BCE, such as Hittite, Luwian and the Indo-Aryan material attested in the Mitanni civilization Egyptian: a stand-alone branch of the Afroasiatic languages confined to Egypt Hurro-Urartian languages, a small family. The Kassite language