Sleep and Temperature

The weather in Vegas is mild right now, and it's that time of the year when I often turn on the air during the day and the heat at night.  The other night I forgot to turn the heat back on, and so it was obviously cooler throughout the night.

However, I noticed that I slept a little sounder than usual that cooler night, and it got me to thinking.  Hunter-gatherers slept outside, and of course at night the temperature naturally drops.  Perhaps then, the body is "expecting" it to be cooler at night.   So could having cooler temperatures at night improve sleep? 

I didn't find a whole lot of research on this.  However, the National Sleep Foundation does state that "cooler temperatures aid sleep".

I will experiment with this and see if it's true.  I have set up my thermostat to have cooler temperatures during the night, and we'll see how it goes.