Fear:

Anxiety (nervousness) is a “hard-wired” emotion that just everyone experiences because it is based on fear, which has survival value. It is very likely the most powerful emotion we feel, and is typically manifested by increased heart, respiration, pulse, and blood pressure. I like to tell my patients that everyone on earth today is a descendent of people who responded well to fear. If our ancestors did not have strong fear responses, they would not have survived confrontations with wild animals and natural diasters. The people who were not good “fear responders” did not survive and get to pass on their genes to us. So fear does have some positive attributes; we just need to learn how to remain mobilized in the face of it. When we perceive that we are not in control of the situation we are in we experience stress which is a particular state of fear.