What is the causes of ethnicity?

In what way did the treaty of Nanjing alter Chinese culture and society forever? Is ratan bhardwaj gotra and bhardwaj gotra are same or not? How do Torres strait islanders tell time? How have inuit homes changed in the last century? Who hate Asian people? Who was sacagawea sold to? What stereo types were often applied to people living in the Appalachian mountains? When was the caste system created and by who? What does 'tribes' mean? What is the country that is the least culturally diverse? Who did Pocahontas married? Why is it that culture is complex whole? What were the chief characteristics and accomplishments of the Aztecs? What is the name for a group of hats? What groups faced hard times during much of the 1920's? How did the Inuit get around? What is the primary difference between a culture that values collectivism and a culture that values individualism? What is Kente cloth and for what is it used? Dominant group vs minority group? What type of clothes do people wear in Ontario?