If you can answer the following question correctly I will give or send you a bag of Skittles, even if I don't know you:
What is the only anatomical feature that is present in humans but in no other primate?  I'm talking about something that completely does not exist in other primates, not just something that's a different shape or size, because there are many of those.  Please send your response by email to indriindri at hotmail dot com.  Come on, don't you want free Skittles?