Comment Re:If race doesn't exist, how is this possible? (Score 1) 312
Not exactly.
It is pure evolution in action stranger=danger. It is a biological adaptation to trust the people that are most like us. You trust your close family more than your more distant family and so on. The easer to see the difference the greater the distrust. From an evolutionary point of view the amount people look, smell, and act alike reflects the amount of common genetic material they share. So you care more about their survival and they care about yours.
Frankly the fact that humans have come so far in ignoring this instinct show just how important community is to humans.