Natural selection is a big influence on how people react to certain situations. Natural selection favors genetic variations that produce adaptive behavior. This is why people that like and can deal with change are more productive. In earlier times, it was all about having enough food and who could avoid diseases, but now the ones that thrive are the people that can fit in. This is why we see people change in order to fit in with the culture, because if they don't they feel that they will be over looked since natural selection looks for the "fittest" people to survive/strive. Also, some of the biggest fears seen today like snakes, and heights are results from past ancestors that saw these things as dangers. These fears have traveled from generation
