Fear of the dark is a common and an almost universal fear for at least a part of our lives (usually some part of our childhood). Though it's not so much the dark itself that we fear, but the unknown -those scary things that might be hiding in the dark. At some age we figure out that what we can't see can hurt us! As we mature, we internalize the real odds of something dangerous hiding in the dark, and that calms us in appropriate situations, but that fear can come back when we are in unfamiliar places. The reason we are all afraid of the dark at times is because that fear gave us an advantage during our evolutionary history.
Remember, for a large portion of humanity's early days, we were far from the top of the food chain. Our ancestors quickly learned that many predators prefer the cover of darkness to hunt and over time that association strengthened into a subconscious absolute: stay out of the dark because that's where the danger is.
While fear of the dark can manifest itself as an acute reaction—like panicked screaming when someone suddenly turns out the lights, or as insomnia, as a recent study conducted at the University of Toronto suggests—it more commonly manifests as foreboding anxiety. The emotion of anxiety plays a specific role in our behavioral responses to stimuli just as the emotions of love, anger, and sadness do, acting to increase our ability to cope with stress and more fully exploit beneficial opportunities.
An article at Gizmodo dips into the specifics of what happens when we confront the scary dark places into which we cannot see, and how we learn to judge its dangers. -via the Presurfer
(Image credit: Flickr user Joe Penniston)