This was something I mentioned in family worship a few days ago -- correct me if my understanding is wrong:

God divided the world not by families, but by languages. The peoples of the world, from the lines of Shem, Ham, and Japeth, all lived together in one city for several generations -- doubtless intermarrying -- until the time of the Tower of Babel. At that time God divided the languages. He did not necessarily divide the languages by families. Any anthropologist will tell you that culture origination is not innate to an ethnic group, but rather a product of many things, chiefly that group's language. A language defines what a people are. A people's ethnic characteristics were not determined by his family post-deluge either - Shem, Ham, and Japeth could not have been so different as to give rise to radically different people groups. Rather, as any geneticist will tell you, ethnic characteristics are produced by the peculiarities of the climate a person lives in and the inbreeding of mutations. All men trace back to Noah, and from thence to Adam. But their differences trace back not to Noah, but to Babel and its immediate fruits.

__________________
Timotheus, servant of the Lord
[(Timothy Merkel - Ellicott City, MD - Trinity Reformed Presbyterian Church)]
Ye who are the warriors of God
And of the law of God
Hope in God, believe in God,
And in God you shall ever triumph