amanda/ flickr We all laugh. But why? If you look closely, youâ€™ll find that humor has very little to do with it. In this episode, we explore the power of laughter to calm us, bond us to one another, or to spreadâ€¦ like a virus. Along the way, we tickle some rats, listen in on a babyâ€™s first laugh, talk to a group of professional laughers, and travel to Tanzania to investigate an outbreak of con...