As I've learned on ABF… .
Europeans and other Eurasians/Asians have very, very fixed mentalities regarding society, culture, religion, and most importantly speaking of all, Ethnicity. Ethnicity in the old world essentially is a post-modern 'tribe' mentality. Ethnicity = Tribe of people, for Europeans, Asians, and Afrikans, etc. New Worlders really don't have proper "Ethnicities" due to our fresh, more recent, (lack of) History.