According to Donald Noel, ethnic stratification will emerge only when specific ethnic groups are brought into contact with one another, and only when those groups are characterized by a high degree of ethnocentrism, competition, and differential power.
Daɣ ta-ite tan Donald Noel,tikarsay n tawset ad tahil s data alwaq wa id taqqimen n tawseten artay nat id ti yadnen tolas alwaq wa id taqqimen tin ojjar daɣ sanat anmizlay n tawsaten, takrikira d tanaya tizlayat.