I always thought my fear of the dark was a silly thing left over from childhood. Now, thanks to science, I've learned the truth. It's a silly thing left over from childhood and from early human history when it wasn't actually so silly. New York magazine gathered some scientific explanations for nyctophobia, or the irrational fear of night or darkness to the layman. In those thousands of years before we tamed the rest of the earth, the dark was where we were in danger of predators and far from the warm glowing hearth of shelter and society. A study published the journal Plos One linked the hunting habits of lions — after 6 p.m., not during a full moon — to man's innate fear of darkness. Those predators can function in the dark whereas we cannot. The instinct to protect ourselves from nocturnal hunters apparently takes more than one and a half centuries post-Thomas Edison to outgrow. What is it we're afraid of in the dark? Everything. Or, well, because we don't know what's there (being the visually focused animals we are), our anxious minds can come up with endless possibilities of the dangers nearby. Of course, most people do unlearn the instinct in childhood through exposure, but a survey in the U.K. found that 40% of respondents admitted to being scared to walk around their own homes without a light on. Another study at Ryerson University in Toronto found that almost half of respondents said they were afraid of the dark, which resulted in sleep problems. What's interesting is that, according to Ryerson assistant professor Colleen Carney, many people don't realize they have a fear of the dark and are attributing their anxiety to something else. "An individual may not be able to fall asleep once it’s dark and their mind starts to wander," Carney told Time. "They think, ‘What if someone breaks into my house?’ Instead of realizing these associations may indicate a fear of the dark, they skip a step and assume they have a fear of burglars."
The solution is exposure or cognitive therapy. Basically, it's what parents try to do when they show their kids repeatedly that the dark is not a scary place. Just as long as we don't have to go back to sleeping near lions.