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Completely Optional Knowledge


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

03:11 | Jan 2nd, 2018

An update on the podcast and some exciting news. Spoiler - the exciting news is a new podcast. Subscribe Now

08:33 | Dec 26th, 2016

Brigitta Green from the perennial winter wonderland of Minnesota has a fitting question for us about ice. After a mysterious, late night howling sound caused “mass slight curiosity” on the streets of St. Paul last winter, she wants to know how it is ...Show More
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10:53 | Dec 13th, 2016

What's the coolest or weirdest official name for a species of plant or animal? And how do they get those funny sounding Latin names anyway?

10:28 | Nov 29th, 2016

Is a watermelon a vegetable? Biologically it’s logical, but does the answer depend where you live?

10:34 | Nov 15th, 2016

Zookeeper Rick asks why why animals see color differently? Dr. Jay Neitz of the University of Washington Department of Ophthalmology says there is more than one factor that accounts for how animals perceive color. Some plants and animals present vib...Show More

10:33 | Nov 1st, 2016

Listener Ross Wintle, driving past a cemetery near his home, wonders if animals other than humans have rituals around death? Barbara J King, professor emerita of anthropology at the College of William and Mary and the author of How Animals Grieve rep...Show More

11:30 | Oct 18th, 2016

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 Wa...Show More

11:59 | Oct 4th, 2016

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 T...Show More

09:28 | Sep 20th, 2016

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, bu...Show More

11:11 | Sep 6th, 2016

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 ...Show More

10:03 | Aug 23rd, 2016

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 wo...Show More

07:55 | Aug 9th, 2016

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 o...Show More

12:25 | Jul 26th, 2016

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 i...Show More

12:05 | Jul 12th, 2016

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...Show More

11:38 | Jun 28th, 2016

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...Show More

10:36 | Jun 14th, 2016

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 An...Show More

10:18 | May 31st, 2016

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 processe...Show More

11:37 | May 17th, 2016

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 partners...Show More

09:30 | May 3rd, 2016

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 ...Show More

08:59 | Apr 19th, 2016

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 h...Show More

08:17 | Apr 5th, 2016

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....Show More

09:18 | Mar 22nd, 2016

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 ...Show More

08:44 | Mar 15th, 2016

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 Garl...Show More

08:27 | Mar 1st, 2016

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 Berk...Show More

09:25 | Feb 16th, 2016

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...Show More

08:15 | Feb 2nd, 2016

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...Show More

08:30 | Jan 19th, 2016

If you could have a head start preparing for an earthquake to hit, wouldn’t you take it? That’s all San Francisco resident Terry Worona wants, and he’s looking to the animal kingdom to get it. To find out if his theory holds up, we talked to Dr. Rach...Show More

08:00 | Jan 5th, 2016

Swimmer Veronica Simmonds wants to know what happens when you take aquatic adventure to the extreme. So we called up ‘aquanaut’ — that’s like an astronaut but under the sea — Jessica Fain, who holds the record for longest time spent living underwater...Show More

08:33 | Dec 8th, 2015

Dr. David Kirby, author of "Lab Coats in Hollywood," digs into that fine line between sublime fantasy and falling flat at the movies. So, what irks scientists at the cinema? Comically rapid evolution, the time-space continuum, animal stereotypes, and...Show More

08:38 | Nov 24th, 2015

Sloths don't really "do" a lot, and yet they've managed to win our hearts time and again. Admitted sloth enthusiast Brooke Ziebell wants to know what's behind the emotions these cute critters manage to conjure. Yale's Oriana Aragon, an expert on huma...Show More

07:54 | Sep 14th, 2015

Brigitta Green from the perennial winter wonderland of Minnesota has a fitting question for us about ice. After a mysterious, late night howling sound caused “mass slight curiosity” on the streets of St. Paul last winter, she wants to know how it is ...Show More

06:16 | Sep 14th, 2015

New Yorker Alex Kapelman has never seen a tornado, and he’s curious: what do they smell like? With more than 20 years of storm chasing under his belt, extreme weather documentarian Warren Faidley has our answer. And no—he didn’t have to enter the eye...Show More

07:30 | Sep 12th, 2015

Space camp alumnus Avery Trufelman from Oakland, California wants to know what the sun sounds like, and so do we! NASA sound and space expert Robert Alexander has our answer, delivered through the wondrous technology of sonification.

09:05 | Sep 11th, 2015

Vancouver meteorologist Kristi Gordon had a not so fortunate on-air experience with an arachnid guest descending on her from above, so she asked us to find out where this “raining spider” came from. Australian naturalist Martyn Robinson explains that...Show More

08:57 | Sep 10th, 2015

On a recent vacation to Costa Rica, Indianapolis, Indiana nurse Amy Gastelum did what we all would if given the chance: she touched a touch-me-not plant. Now, she wants to know why the plant recoiled at her touch. Evolutionary ecologist Monica Galian...Show More