There appears to be an evolutionary need for humor, so the unknown theory here could actually shed some light.
Also, laughing yoga. http://www.youtube.com/watch?v=ahhN3Ryw4O4
There appears to be an evolutionary need for humor, so the unknown theory here could actually shed some light.
Also, laughing yoga. http://www.youtube.com/watch?v=ahhN3Ryw4O4