When the only, ONLY, difference between two people is pigmentation, then there really is no difference at all. Cut those people open and the exact same thing will fall out, from the exact same places (unless of course one is like.. deformed.. o.0)
The same heart pumps blood through the body.
The same lungs take in and supply the cells with oxygen.
The same brain sends the same impules to create the same emotions.
Show me one, ONE, physical, emotional, or psychological, difference between the races besides pigmentation, and we'll talk further.

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