Geography of Asia though the Middle East is a division of Asia. The demarcation between Asia and Africa is the isthmus of Suez and the Red Sea. The border with Europe starts with the coast of the eastern Mediterranean, even though Turkey in the Near East extends partly into the Aegean Islands and includes Istanbul on the European side of the Bosphorus. On the north the boundary between the continents of Asia and Europe is commonly regarded as running through the Dardanelles, the Sea of Marmara, the Bosporus, the Black Sea, the Caucasus Mountains, the Caspian Sea, the Ural River to its source,
African admixture in Europe Europe may have a common origin in Asia (e.g. Y haplogroups R1, and some paternal haplogroup T and U subclades). One subclade of haplogroup U, namely U6a1, is known to have expanded from northern and eastern Africa back into Europe even though haplogroup U6 is considered to have originated in the Middle East. Other lineages are known to have moved from Europe directly into Africa, for example mitochondrial haplogroups H1 and H3. Such bidirectional migrations between Africa and Eurasia complicate the task of defining admixture. One proposed example of Holocene gene flow from Africa to Europe, via the Middle East,