How do you find out why we laugh? With tickling, of course! Gorillas and other great apes appear to love being tickled, and sound like they’re laughing just like us. Animal biologist Marina Davila-Ross thought tickling might connect humans and great apes - and hold the clues to the origin of laughter. To find out, she assembled teams of ticklers in an experiment full of giggles. It’s the silliest science you’ve ever heard, but the discoveries will blow your mind. Learn more about laughter in animals and humans in our interview with Marina Davila-Ross. Listen to the bonus interview episode available to Patrons who support Tumble at the $1/level or higher, at patreon.com/tumblepodcast. See videos of gorillas being tickled, and more free educational resources on our blog at sciencepodcast.com.