I can echolocate. I didn't realize that at first, but it's what enables me to get around just fine in pitch darkness. Try this yourself, either blindfolded or

I can echolocate. I didn't realize that at first, but it's what enables me to get around just fine in pitch darkness. Try this yourself, either blindfolded or in a darkened room. Start with one that has nothing in it, so you don't trip over the furniture. At first hold your hand out in front of you so you don't slam into the wall. Eventually you will grow confident enough that you don't need to anymore. There is a distinctly different sensation in my ears when I am near a wall, than when I am away from the walls. It's not something I hear exactly, but a sense of pressure coming from the nearby wall. I'm pretty sure that I am feeling the pressure of subsonic acoustic standing waves. I have no fear whatsoever of the dark, even to the point that I enjoy solo scuba diving, at night, without a flashlight. That's profoundly dangerous: kids, don't try it at home.