Scientists are beginning to link animal facial expressions to emotions, making it possible for us to understand how they feel.
If you're looking online for new love, a new job or just to meet up with new friends, then a lot rests on the face you present to the world.
What happens when the face is no longer the primary means of expression?
Just a few hours after birth, infants show a preference for human faces. Over the next few months, they learn from facial expressions.