Maybe it's because we just take the classics so seriously, but Greeks and Romans are seldom thought of as sitting around belly-laughing at the latest knock-knock jokes. According to an article in today's California Chronicle, we may want to revise our mental image and yuck it up a bit.
Classical professor Mary Beard has discovered a Roman manuscript dating from the 3rd Century AD containing 265 honest to goodness ancient jokes and riddles. Interestingly, some of the jokes sound positively modern. Like the 'Doctor, doctor' joke where the patient says "Doctor, when I wake up in the morning I'm dizzy for half an hour, then I'm ok." Doctor: "Well, then, just wait a half an hour before getting up."
It's not clear whether the ancient book was a comedian's jokebook or whether some ancient author was trying to collect and classify the jokes. But, they have been preserved which means the next time your hear an old joke, it might be very old indeed.