After giggling at this for about a minute, I'm wondering if that's why they do it... funny faces make us happy. Wouldn't it be nice if we turned from sexy faces to silly faces? Look at how underutilized other means of communicating affection and making people happy have become. If people stop feeling like only a sexy look would make them looked at and make people feel good, maybe things would be more fun. It's unfortunate how few people will return the favor if i make a funny face at them... But when it's appropriate to make sexy-eyes, then we both feel loved.