And .. what is your proof of that ..??
Beyond these periods, Mahometan tradition is entirely worthless. It is not original, but taken at second hand from the Jews. Mahomet having claimed to be of the seed of Ishmael, the Jewish Rabbins who were gained over to his cause endeavoured to confirm the claim from the genealogies of the Old Testament and of rabbinical tradition. In the attempt to reconcile these with the received notions of the Arabs, Joktan (whom they found in Scripture to be an early immigrant into Arabia) became identified with Cahtan, the great ancestor of the southern tribes; while Mahomet's paternal line (which he himself declared could not be followed beyond Adnan, that is, about a century before the Christian era) was nevertheless traced up by fabricated steps, eighteen centuries farther, to Ishmael2. Both the legends and the ethnological assumptions or Mahometans regarding events prior to the Christian era, being thus derived directly from the Jews, possess no value of their own, and as evidence must be entirely rejected. They consist either of simple plagiarism, or they refer to Arabian personages and events of a very modern date, confounded in a rude and even ludicrous manner with the patriarchal characters and stories of the Old Testament2. http://answering-islam.org.uk/Books/Muir/Life1/chapter2.htmB. Genetic. Mitochondrial drift studies on Middle Eastern Jews show that their closest relatives genetically are certain non-Arab groups in Iraq. The reason for this is that Abraham came from Mesopotamia and the Jews came from Abraham. If Ishmael were the ancestor of the Arabs, they would share a similar ancestry with those same non-Arab groups in Iraq and a close ancestry with Middle-Eastern Jews. They show neither. The genetics underscore the genealogy.