Have you ever wondered why being around children, who smile so frequently, makes you smile very often? A recent study at Uppsala University in Sweden found that it's very difficult to frown when looking at someone who smiles. You ask why? Because smiling is evolutionarily contagious, and it suppresses the control we usually have on our facial muscles. Mimicking a smile and experiencing it physically helps us understand whether our smile is fake or real, so we can understand the emotional state of the smiler.