Historically, a human fear of the dark stemmed from our lack of night vision and inability to see predators. Around the time of the Australopithecus (ancient apes that closest resembled what we know today as hominids), the apes exchanged their night vision (lots of rods, few cones) for colour vision (lots of cones, fewer rods) so that they could pick fruit out of trees. So, fear of the dark is literally, perfectly natural. I'm 19 and still afraid of the dark (especially pitch blackness; makes me panic and feel like I've gone blind). Oddly enough, natural dark, outside with lots of stars, while still making me uneasy, doesn't bother me as much as the artificial darkness of a house at night, I guess it's because there are so many more unnatural shadows and patches of eerie light to be misinterpreted by an overactive mind.
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"Survival is insufficient" - Seven of Nine
Diagnosed with ASD level 1 on the 10th of April, 2014
Rediagnosed with ASD level 2 on the 4th of May, 2019
Thanks to Olympiadis for my fantastic avatar!