Crying as an expression of emotion appears to be uniquely human behavior. Other animals may tear up because of irritants in their eyes, but only humans shed tears at times of extreme sadness or joy.

Photo credit: Shutterstock.com / AJR_photo. That box of tissues isn’t just for mopping up your emotions—those tears you’ve been holding back at work, in traffic, or during that commercial with the ...

Why do we cry? Faced with overwhelming joy or grief, our eyes well up and tears stream down our cheeks. Crying is one of the most defining human experiences one can have. And yet, it's an evolutionary ...