How and when did jokes start, and why?

Knock knock! Everybody loves a good joke, but how did they start? And why do we think they’re so funny? We asked Brains On producer and resident funny expert Anna Goldfield to give us the lowdown on jokes!  Got a question that’s tickling your curiosity? Send it to us at BrainsOn.org/contact, and we’ll get to the punchline. See omnystudio.com/listener for privacy information.