It ' s easier not to think of race as where they come from centerbased , but as how a society defines its borders i . e . who gets thrown into what category . This makes a lot more sense because mixedrace people can be 50 % genetically mixed and 50 % geographically mixed , but a society will often group them in a consistent way e . g . WhiteBlack mixed race in America is often considered to be BlackUsing this , you can look at how a society ' s groupings change . A really striking one is to look at the US census categories if I remember correctly , Chinese Japanese Filipino all used to be separate , but then they were grouped into the broader Asian race which is pretty foreign to any of those home cultures . Another example is the change in what is considered White Irish , Italian , Greek , and Jewish would not have been considered as such during their respective immigrations , but over time were assimilated into the concept of Whiteness . Of course , these dynamics are subject to several forces . Coalition politics often pushes grouping of minorities , for example .