Genetic admixure : When people from different groups interbreed . There have been many instances of this happening . For instance , genetic material from French people suggests an intermixing between northern and southern Europeans and northern Africans , between 785 and 1,385 years ago , but the event itself is still unclear . For example, the Amish are a group that has lived in one place for hundreds or thousands of years and they still speak English as their first language ( though not all Amish do ).
Genetic admixure : When people from different groups interbreed . There have been many instances of this happening . For example, the Amish are a group that has lived in one place for hundreds or thousands of years and they still speak English as their first language ( though not all Amish do ).