from an article on the internet...
A simple bawdy joke from ancient Egypt (2,000-year-old one-liner), this gag was written just as the last remnants of the Roman Republic collapsed.
The joke is believed to have been written around the same year that Marc Anthony and Cleopatra killed themselves by snakebite; they certainly wouldn't have died laughing.
"Man is even more eager to copulate than a donkey.
His purse is what restrains him."