It worked very similarly in the Pleistocene forests when primitive man was hunting. Only the strongest survived and fear is what drove them to develop methods of survival, such as living in tribes to make predators less likely to attack. Primitive humans also developed tools in fear of survival during the Paleolithic epoch nearly two point six million years ago and fear has been there with humanity …show more content…
Fear, as defined by the New Oxford American Dictionary, is an unpleasant emotion caused by the belief that someone or something is dangerous, likely to cause pain, or a threat. The sensation of fear is a wave of chemicals that affects the brain, the largest amount being adrenaline, which prepares the body for either fleeing from or fighting off potential danger. In a study done by Doctors Pernet A, Walker M, Gill G, Orskov H, Alberti K, and Johnston D, they studied the affects of adrenaline on the body and their results showed adrenaline affected the body in a variety of ways. Their research showed that adrenaline accelerates the breathing rate, or hyperventilation, increases muscle tension, which includes the muscle connected to a hair follicle, which causes it to contract causing “goose bumps”, or piloerection, which serves to make a cold person warmer or make frightened animals look more impressive. Adrenaline also increases sweating to release excess heat, increases blood glucose levels, or hyperglycemia, to give a burst of energy, causes the sensation of “butterflies in the stomach” or dyspepsia, and increases heart rate to allow blood to circulate faster allowing oxygen to reach all cells more