We start this story off with a question. Are human beings innately violent?

Then we head to East Africa with Stanford neuroscientist Robert Sapolsky, who spent his summers studying wild baboons there. Baboons are a textbook example of a hierarchical, male-dominated, and aggressive society. But one day, Sapolsky noticed that a troop of baboons became unexpectedly gentle. They deviated from the usual aggressiveness so characteristic of them and groomed each other. The key question was how do these guys unlearn their entire childhood culture of aggression, something supposedly built-in? Sapolsky tells us that tale — a moment he describes as one of the best science moments of his life.

For more: Read Robert Sapolsky’s account of his 21 years studying baboons in Kenya.

Radiolab was created by Jad Abumrad and is edited by Soren Wheeler. Lulu Miller and Latif Nasser are our co-hosts. Dylan Keefe is our director of sound design. Our staff includes: Simon Adler, Jeremy Bloom, Becca Bressler, W. Harry Fortuna, David Gebel, Maria Paz Gutiérrez, Sindhu Gnanasambandan, Matt Kielty, Annie McEwen, Alex Neason, Valentina Powers, Sarah Qari, Sarah Sandbach, Arianne Wack, Pat Walters and Molly Webster. Our fact-checkers are Diane Kelly, Emily Krieger and Natalie Middleton. Production help from Tanya Chawla. Sound mixing by Joe Plourde.

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Support for Terrestrials is provided by the Simons Foundation, the Arthur Vining Davis Foundations, the Kalliopeia Foundation and the John Templeton Foundation.

We start off in a cathedral full of animals – hermit crabs, parrots, hamsters, dogs, cats and bunnies – being blessed. We then wonder, do the animals feel grace? What do we really know about what goes on inside an animal’s mind? Do they also experience gratitude, despair or anger? How much emotionality do humans and animals share? And can we measure it?

We get the story of a rescued whale that may have found a way to say thanks to its rescuers. And then we speak to behavioral scientist Clive Wynne, and head of the Dog Cognition Lab at Barnard, Alexandra Horowitz, to decipher the whale’s behavior.

Guests in the episode include: Mick Menago, Tim Young, James Moskito, Holly Drewyard, Clive Wynne and Alexandra Horowitz.

For more: Read “Inside of a Dog” by Alexandra Horowitz.

Radiolab was created by Jad Abumrad and is edited by Soren Wheeler. Lulu Miller and Latif Nasser are our co-hosts. Dylan Keefe is our director of sound design. Our staff includes: Simon Adler, Jeremy Bloom, Becca Bressler, W. Harry Fortuna, David Gebel, Maria Paz Gutiérrez, Sindhu Gnanasambandan, Matt Kielty, Annie McEwen, Alex Neason, Valentina Powers, Sarah Qari, Sarah Sandbach, Arianne Wack, Pat Walters and Molly Webster. Our fact-checkers are Diane Kelly, Emily Krieger and Natalie Middleton. Production help from Tanya Chawla. Sound mixing by Joe Plourde.

Sign up for Radiolab for Kids’s newsletter! It includes short essays, recommendations, and details about other ways to interact with the show. Sign up here.

Radiolab for Kids and Terrestrials are supported by listeners like you. Support Radiolab by becoming a member of The Lab today.

Follow Radiolab on Instagram, X Facebook, Threads and TikTok @radiolab.

Support for Terrestrials is provided by the Simons Foundation, the Arthur Vining Davis Foundations, the Kalliopeia Foundation and the John Templeton Foundation.

Artist Ashley (Ash) Eliza Williams was so shy growing up that they found it hard to speak to people. Instead, they withdrew from the world of humans and found comfort in the forest, where they spent hours exploring, scavenging, and collecting — eventually discovering lichen. They began painting portraits of lichen’s wild, colorful, and fuzzy shapes.

In time, Ash learned that lichen is actually a composite organism, a mixture of two species — algae and fungi — working together to live. This idea originally challenged evolutionary theory so much that scientists didn’t believe it. But lichen had much more to teach us.

Chef Prashanta Khanal fills us in on the food science of lichen, and how its collaborative powers also extend to making certain foods healthier! Learning that lichen draws its strength from collaboration eventually encouraged Ash to break out of their shell and reconnect to the world, where they would find not just friends and collaborators, but their true love.

Since the release of this podcast, artist Ash Eliza Williams goes by Ash and uses they/them pronouns.

Check out Ash Eliza Williams’s beautiful paintings.

Visit chef Prashanta's cooking blog, the Gundruk, for more on Nepali food history and recipes.

This episode features punk rock legend Laura Jane Grace, who makes a musical cameo on the song The Fuzzy Ruckus. Watch the music video and find the link to stream on our songs page.

Terrestrials was created by Lulu Miller with WNYC studios. This episode was produced by Brenna Farrel, Mira Burt-Wintonick, Alan Goffinski, Ana González, Tanya Chawla, Joe Plourde, Sarah Sandbach, Valentina Powers and Lulu Miller. Fact-checking by Diane Kelly. Transcription by Caleb Codding.

Special thanks to Siya Sharma-Gaines, Niran Bhatt Scharpf, Scott LaGreca, and Sarita Bhatt.

Our advisors are Ana Luz Porzecanski, Andy J. Pizza, Anil Lewis, Dominique Shabazz, Liza Demby, Princess Daazhraii Johnson and Tara Welty.

Learn more about storytellers, listen to music, and dig deeper into the stories you hear on Terrestrials with activities you can do at home or in the classroom on our website,

Terrestrialspodcast.org.

Badger us on social media: @radiolab and #TerrestrialsPodcast or by emailing us at terrestrials@wnyc.org.

Sign up for Radiolab for Kids’s newsletter! It includes short essays, recommendations, and details about other ways to interact with the show. Sign up here.

Radiolab for Kids and Terrestrials are supported by listeners like you. Support Radiolab by becoming a member of The Lab today.

Follow Radiolab on Instagram, X Facebook, Threads and TikTok @radiolab.

Support for Terrestrials is provided by the Simons Foundation, the Arthur Vining Davis Foundations, the Kalliopeia Foundation and the John Templeton Foundation.