Completely Optional Knowledge

Completely Optional Knowledge


The podcast where we answer the questions you never knew you had. Produced by Andrew Norton with music by Breakmaster Cylinder, brought to you by Greenpeace.


Why Do We Laugh At Pain?  

Listener Matthew Hollingshead, a skateboard enthusiast, asks why it’s so funny to watch people get hurt. We’re not necessarily talking about critical injuries, more like America’s Funniest Home Videos style failures, pain, and embarrassment. Caleb Warren, an Assistant Professor of Marketing at the University of Arizona helps us answer this question and feel a little better about finding joy in other people’s “hilarious misery”. If you like Completely Optional Knowledge, help support the show:

Do Animals Have Eating Contests?  

Hilah Johnson hosts a show about cooking (and, naturally, eating)and she came to us with a very on-brand question. Do animals have eating contests? We spoke to biologist Elise Huchard to get the answer. Check out Hilah's cooking show! Find her on Twitter @hilahcooking.

What's Quantum Teleportation?  

Listening to Shohini Ghose talk about what would happen if a human reached light speed in Episode 16, Fred Papon of Australia wanted to know more about her research into quantum teleportation. Ghose reveals that teleportation has already happened, but don’t expect someone on the train with you to disappear after saying “Beam me up Scotty.”

How Do Animal Taste Buds Work?  

Dallas College professor Patrick Moore, seeing his dog Abbey eating her own poo and swallowing dirty socks, wonders how animal tastebuds work. Danielle Reed, associate director of the Monell Chemical Senses Center, takes a break from feeding her cat Diet Coke to talk about the chemical properties of taste. Both cheese and sweaty socks smell like isovaleric acid. Dogs being omnivores unconstrained by the social cues that govern human behavior are going to go ahead and see if that sock is food. Host Andrew Norton would rather have listeners thinking about Mac and Cheese but he has his own taste issues. Maybe it’s in genetics?

Why Do Siblings Have Rivalries?  

Molly and John Knefel, sister and brother co-hosts of the daily podcast “Radio Dispatch” wonder why siblings become rivals. Naomi White, PhD, of Cambridge University, explores the evolutionary and cultural roots of sibling conflict and finds that working things out with your sister or brother teaches important lessons about life and relationships.

What Does the Sun Sound Like? [rerun]  

Inspired by freeze-dried ice cream at Space Camp, podcast producer of 99% Invisible Avery Trufelman wonders what the sun really sounds like setting aside the hokey furnace effect shown in movies. Knowing that no sound waves can travel in the vacuum of space, fellow space camper and Completely Optional Knowledge host Andrew Norton finds a marvelous audible version of satellite data from sonification specialist Robert Alexander who trains heliophysicists at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, to pick out subtle differences by listening to satellite data instead of looking at it. So get some astronaut ice cream and join in by pushing the “play” button.

Can Music Make You Hungry?  

Breakmaster Cylinder, creator of the Completely Optional Knowledge theme music, wonders if music can be used to trigger specific responses in people. Jessica Grahn of the Music and Neuroscience Lab at Western University explores ways that music can influence people and create personal playlists for happier healthier lives. For host Andrew Norton a turkey sandwich might be in his future. Listen to Breakmaster Cylinder . Find out more about how beats and music affect the brain

What Is Wind?  

Lauren Ober is the host of WAMU's The Big Listen. She wanted to know the answer to a relatively simple question - what is wind? With help from UCLA mathematician Marcus Roper, she got an answer plus something unexpected: the fascinating way mushrooms catch a breeze by making it themselves.

How Do You Take Great Photos From Space?  

Jonathan Mehring has photographed all over the world, but there’s one place he hasn’t been yet that he’s dying to learn about: outer space. So we talked to someone who’s spent a whole year in space and taken thousands of photos while he was out there, astronaut Don Pettit. As we learn, even the simplest photography tasks are made difficult when you’re orbiting the Earth in zero gravity. Listen in for Don’s pro-tips on how to capture amazing photos from outer space! Check out Don’s photos at or on Twitter @astro_pettit (and follow Jonathan @mehringphoto while you’re at it). The photo used with this episode comes courtesy of the Earth Science and Remote Sensing Unit, NASA Johnson Space Center.

Are There Lazy Ants?  

Have you ever seen an ant just … hanging out? Completely Optional Knowledge listener Bryan Fox hasn’t, and it’s getting under his skin. To get Bryan the scoop on whether ants’ seemingly steadfast work ethic is just a facade, we called up biologist Anna Dornhaus. Anna explains to us how ants have evolved into highly specialized roles that keep their colonies running smoothly, and one of those roles is just … hanging out.

Who Governs Space?  

Who makes the rules in outer space? That’s what Completely Optional Knowledge listener Tim Burberich called in to find out. So we got in touch with space lawyer Joanne Irene Gabrynowicz (dream job alert) who walks us through highly political processes and treaties that allow humans to get along in places like the International Space Station. Houston, we have a treaty.

What's the Most Surprising Partnership Between Animals?  

Emily Schorr Lesnick is the co-host of the SoulGlo podcast, a show about how diversity helps humans thrive. Naturally, she wants to find out if diversity in nature helps animals thrive the same way it helps us. Thinking about unlikely animal partnerships might conjure images of kittens riding turtles, or fish and birds joining forces, but researchers Michele Lanan and Mary Jane Epps bring us some suprising (and actually true) examples of ways life in the wild couldn't continue without what biologists call 'mutualism.'

Do Invincible Creatures Exist?  

Jessica Abel is working on a new book about Mars (Trish Trash: Rollergirl of Mars - available in November 2016) - which got her wondering about the most amazing creatures here on earth. Dr. Roberto Guidetti gives us the lowdown on the incredible and nearly invincible animals he studies. For more on Jessica Abel's upcoming book visit:

What If I Went Light Speed?  

Tom Sortodden wants to know what would happen if he went the speed of light. Physicist Shohini Ghose of Wilfrid Laurier University explores the implications of the theory of relativity, abstract art, time and distance and infinite force. Prepare to have your mind blown or a few circuits in your brain shorted.

What Animal Has The Stinkiest Farts?  

Award-winning filmmaker Troy Hale comes to Completely Optional Knowledge to find out which animal has the smelliest farts. Zookeeper Rick of the San Diego Zoo is in the right job to sniff out the answer. He works with 60 different species of animals. “Whether you are in the second grade or in your second retirement, when you hear a rhinoceros fart, you laugh, it’s funny,” he says. Listen and learn about the winds that blow around the animal kingdom. If you are intrigued, you might want to conduct your own survey. After all it’s not always the dog that did it.

What Sounds Can't I Hear?  

Annie McEwen has great hearing — but she's still only human — so she's wondering what sounds are out there that she's not able to pick up. To find the answer, we spoke to Milton Garces of the University of Hawaii's Infrasound Laboratory. He tells us about the constant din that eludes our futile human ears. Image credit: Flickr user Nickolai Kashirin (

Have Whale Songs Changed Over Time?  

Music critic Stacey Anderson has listened to a lot of songs in her time. So many, in fact, that she’s grown a bit bored of human music. Now she’s curious about the famous crooners of the deep blue: whales. We spoke to humpback whale expert Ellen Garland to find out what makes whales sing what they sing.

Do Animals in the Wild Get Drunk?  

If you give a mouse a vodka tonic, will he even drink it? That’s the question Ben Harrison — host of the Let’s Drink About It podcast — has brought to Completely Optional Knowledge. And who better to give us our answer than Dr. Robert Dudley, UC Berkeley biologist and author of “The Drunken Monkey.” Disclaimer: no wild animals were intoxicated in the making of this podcast (though the same cannot be said for human animals).

What Is the Fastest Insect in the World?  

Listener Stephen Rang wants to know how fast he would have to run (or drive, as it turns out) to flee the world’s fastest known insect. We go off to the races with the North Carolina Museum of Natural Sciences’ Chris Goforth, who informs us that this particular insect can reach flying speeds of up to 70 mph — and it’s probably not one you would expect.

How Do Animals Choose Their Leaders?  

Election season is upon us, and that means choices. If you’re still on the fence about who to vote for, maybe you’d like to take a cue from ants, whose prospective leaders duel with their antennae. We’ve got biologist Clint Penick, PhD on the show to guide us through how strikingly similar animals’ electoral behaviors are to our own.

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