Humans 'hear' through their skin

I've thought along these lines before, the way we can perceive things without focusing on them (like when you know someone is looking at you when you can't see them), especially when it comes to feeling whether you're close to something, my theory is that heat radiated from the skin reflects off the surface and the skin is sensitive enough to pick it up.

Goes to show the skin is far more complex than we imagine.

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