Well, it's probably combination of different factors; region, how often one race encounters another, how one is raised, etc. The fact is that the human eye isn' trained nor is used ta seein' details and features of another race that it doesn' encounter frequently. In others words, if one lived on an island where one didn' encounter any other than one's own; let's hypothetically say white. Now lets say that ur island get visited by another race, hypothetically oriental, wouldn' it b difficult for ur eye ta discern the different features of each individual of that race just as it would b equally difficult for them ta discern urs? I believe that this plays a huge factor in this behavior. Because most whites do not encounter many orientals in their lifetimes, their eyes r unable ta discern the distinctive features of each individual of that race and the reverse could b said ta b true too, or any race for that matter. This is 'cause the eye; and so thus the brain; isn' trained, nor is used ta encounterin' and so thus able ta pick out individual; distinctive features that mark a person of a certain race as unique. This is somethin' that requires time and more frequent encounters wit, not jus' individuals of said race, but the race in it's entirety or lotsa trainin' for an entire race, both; of which; is extremely difficult. So thus, it would b extremely difficult ta end such behavior.