Our internal clock, or circadian rhythm, is a wonderful, interesting concept.
Yesterday afternoon, I was feeling so exhausted so I laid down to read for a little bit and set my alarm to get up for class, just in case I fell asleep. Low and behold, I fell asleep for almost an hour and when I awoke for my 4pm class at 3:30, instead of 3:15 like I had set my alarm for, I freaked out, but then realized how cool it was that my internal clock woke me up, or so I think!
How does our body know when we should wake and sleep? Well, it's based on the rotation of the Earth and usually the light/dark cycle of day and night. But, how does it work during the day, when we nap? I have no idea. But I think it's pretty great.
