Dreams and be fascinating, scary, and downright weird. Everybody dreams even if we wake up and can't remember a single thing from our last night. But why does our brain have a fantasy or hallucination while we sleep?

Did you know humans aren’t the only animals that hum while they work? Gorillas will sing their own Gorilla tunes and hum happily. Some Gorillas will hum a low sound close to the sound humans make, but...