Racism and ethnocentrism were two popular schools of thought. Each different society claimed to be better than its neighbor. To assess the situation correctly, however, one would have to state that each diverse culture possesses certain physical and mental traits that make it more suited to their particular geographical region. Each person from a different region possesses their own personal survival tool kit. These survival tool kits are evident in the physical appearance of humans.
Skin color is determined by the climate a person lives in.
In very warm climates, a person's skin will be very dark. This results from generations upon generations of past occupants' exposure to the sun. Over time the skin produced more and more melanin, the color causing agent in skin that reacts to the sun, as it was brought out by exposure to the sun to protect the skin from overheating and make it more resistant to cancer-causing agents of the sun. In contrast, people from colder climates tend to have lighter skin because the extra protection from heat is not needed. Another physical aspect of the human body is evident in the shape of a person's nose.