The Slowpoke: How Sloths Grow Invisibility

Sloths are the slowest mammals on Earth. How can a creature that moves so slowly survive in a world that moves so fast? Zoologist Lucy Cooke helps us rethink everything we know about sloths and their slowness. We follow a sloth named Nacho from a rainforest to a nightclub, trek deep into mangrove swamps to find a rare pygmy sloth and uncover the secret that allows sloths to evade even the deadliest predators. Hint: it has to do with a special kind of invisibility. For more, check out Lucy’s A Little Book of Sloth and her sloth calendar ! Terrestrials was created by Lulu Miller with WNYC. This episode was reported and produced by Alan Goffinski, with sound design by Mira Burt-Wintonick. Sarah Sandbach is our Executive Producer. Our team also includes Ana González, Tanya Chawla and Joe Plourde. Factchecking by Natalie Middleton. Our advisors for this show were Liza Demby, Ana Luz Porzecanski, Nicole Depalma and Carly Ciarrocchi. Special thanks to José Pablo Guzmán García , Dr. Sammy Ramsey and Lucy Cooke . In more exciting news, we just created the first ever Terrestrials Jigsaw Puzzle ! It’s a scene of all the creatures we’ve featured on Terrestrials so far, made by artist Arthur Jones. It can be yours for the simple price of supporting Terrestrials by joining our brand new Explorers Club! You get all types of perks like extra Alan songs, ad-free listening and this puzzle for the month of December! Visit TerrestrialsPodcast.org/donate . Thank you for all your support. Support for Terrestrials is provided by the Simons Foundation, the Arthur Vining Davis Foundations, and the John Templeton Foundation. A reminder that Terrestrials also makes original music! You can find ‘Gotta Slow It Down’ and all other music from the show here . HEY GROWN-UPS! Love the show? Leave us a ⭐⭐⭐⭐⭐ rating and review on your podcast app—it helps curious listeners find us! Terrestrials is made possible in part by listeners like you. Support the show by joining The Explorers Club —and we’ll send you a special puzzle as a thank-you gift from our team! We want to hear from you! Share your thoughts about Terrestrials with us .

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The Slowpoke: How Sloths Grow Invisibility is an episode from Radiolab for Kids by WNYC.

This episode is 00:33:14 long.

This episode was published on Dec 18, 2025.

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