Where did the different races originate?

Tweet

The whole question is: Since God created Man from the dust of the earth, original man logically had to be the color of sand, which is closely represented by caucasian. If this is the case, how did the seperate races develop? We now have people with black (actually more of a very dark brown) skin, olive, yellowish (asian), light brown (hispanic, indian), and red (native american). How could this many skin colors come from the same 2 people? This is assuming that Adam and Eve were both of the same race. Please do not take this as a racist subject, as it is not intended to be. Nor do I feel in any way that white is supreme over any other just because I assume that Adam and Eve were the same color as the sand.