Yes. I am seriously afraid of the dark. I'm not sure exactly why though.
I'd assume it's the feeling of helplessness, the same way the ocean scares me. Sure I may be a nearly perfect species for the set circumstances I live in, but once I enter someone else's territory, I'm no longer at the top. I am not necessarily afraid of anything happening, it's just the "what ifs" that cloud my reasonable judgement.
it's pretty odd to think that long ago, humans were scared of the outside world, and believed caves were a god-send. But now? Caves are creepy as fuck.
I have a very wild imagination, but it only shows in the dark.