Our emotions are thought to exist because they have contributed to our survival as a species. Fear has helped us avoid dangers, expressing anger helps us scare off threats, and expressing positive emotions helps us bond with others. From an evolutionary perspective, an emotion is a kind of “program” that, when triggered, directs many of our activities (including attention, perception, memory, movement, expressions, etc.). For example, fear makes us very attentive, narrows our perceptual focus to threatening stimuli, will cause us either to face a situation (fight) or avoid it (flight), and may cause us to remember an experience more acutely (so that we avoid the threat in the future). Regardless of the specific ways in which they activate our systems, the specific emotions we possess are thought to exist because they have helped us (as a species) survive challenges within our environment long ago. If they had not helped us adapt and survive, they would not have evolved with us.