Hi, all; I haven't visited Biology before, so forgive me if this has been addressed already. It's a pretty unimportant question, but it's been nagging me all day. I've always noticed that people's mouths can stand higher temperatures than their hands, and just got to wondering why. Do you figure that it's because of saliva, purely coincidental, or could it be a trait that evolved after the discovery of fire to keep us from burning our digestive tracts on something that we've just cooked? Do other primates share it?