Richard Prum says there's a lot that traditional evolutionary biology can't explain. He thinks a neglected hypothesis from Charles Darwin — and insights from contemporary queer theory — hold the answer. Plus: You won't believe what female ducks use for contraception.

• SOURCE:
  • Richard Prum, professor of ornithology, ecology and evolutionary biology at Yale University.

• RESOURCES:
  • "Stop Your Populist Grandstanding Over Wendy’s ‘Surge Pricing’," by Catherine Rampell (The Washington Post, 2024).
  • "Dynamic Pricing Tech May Brighten Retail Bottom Lines and Put Consumers in the Dark," by Kristin Schwab and Sofia Terenzio (Marketplace, 2024).
  • Performance All the Way Down: Genes, Development, and Sexual Difference, by Richard Prum (2023).
  • The Evolution of Beauty: How Darwin's Forgotten Theory of Mate Choice Shapes the Animal World — and Us, by Richard Prum (2017).
  • "Duck Sex and the Patriarchy," by Richard Prum (The New Yorker, 2017).
  • "Dinosaur Feathers Came before Birds and Flight," by Richard Prum and Alan Brush (Scientific American, 2014).
  • "How Chickens Lost Their Penises (And Ducks Kept Theirs)," by Ed Yong (National Geographic, 2013).
  • "Media Attacks Duck Genitalia Research," by Emma Goldberg (Yale Daily News, 2013).
  • "Mate Choice and Sexual Selection: What Have We Learned Since Darwin?" by Adam G. Jones and Nicholas L. Ratterman (PNAS, 2009).
  • "Development and Evolutionary Origin of Feathers," by Richard O. Prum (Journal of Experimental Zoology, 2002).
  • The Blind Watchmaker: Why the Evidence of Evolution Reveals a Universe without Design, by Richard Dawkins (1986).
  • "Display Behavior, Foraging Ecology, and Systematics of the Golden-Winged Manakin (Masius chrysopterus)," by Richard Prum and Ann Johnson (The Wilson Bulletin, 1987).
  • The Selfish Gene, by Richard Dawkins (1976).
  • The Descent of Man, and Selection in Relation to Sex, by Charles Darwin (1871).

• EXTRAS:
  • "Is Gynecology the Best Innovation Ever?" by People I (Mostly) Admire (2024).
  • "The Price of Doing Business with John List," by People I (Mostly) Admire (2022).

Thomas Hildebrandt is trying to bring the northern white rhinoceros back from the brink of extinction. The wildlife veterinarian tells Steve about the far-out techniques he employs, why we might see woolly mammoths in the future, and why he was frustrated the day the Berlin Wall came down.

• SOURCES:
  • Thomas Hildebrandt, head of the department of reproduction management at the Leibniz Institute for Zoo and Wildlife Research and professor of wildlife reproduction medicine at the veterinary faculty of the Freie Universität Berlin.

• RESOURCES:
  • "An Inside Look at the Embryo Transplant That May Help Save the Northern White Rhino," by Jeffrey Kluger (TIME, 2024).
  • "Mud, Bugs, and Dung: How Rhinos Shape Their World," by Rinjan Shrestha (World Wildlife Fund, 2022).
  • "The Last Two Northern White Rhinos On Earth," by Sam Anderson (The New York Times Magazine, 2021).
  • "Embryos and Embryonic Stem Cells From the White Rhinoceros," by Thomas B. Hildebrandt, Robert Hermes, Cesare Galli, et al. (Nature Communications, 2018).
  • "Loss of a Species – A Giant, Extinct," by Thomas Hildebrandt (TED, 2017).
  • Colossal.

• EXTRAS:
  • "Why Do We Still Teach People to Calculate?" by People I (Mostly) Admire (2024).
  • "What’s Stopping Us From Curing Rare Diseases?" by Freakonomics, M.D. (2023).
  • "We Can Play God Now," by People I (Mostly) Admire (2022).

She is one of the best basketball players ever. She’s won multiple championships, including five Olympic gold medals and four W.N.B.A. titles. She also helped negotiate a landmark contract for the league’s players. Sue Bird tells Steve Levitt the untold truth about clutch players, her thoughts about the pay gap between male and female athletes, and what it means to be part of the first gay couple in ESPN The Magazine’s Body Issue.

• SOURCE:
  • Sue Bird, former professional basketball player.

• RESOURCES:
  • "‘We’re Betting on Ourselves’: Why WNBA’s Landmark New Deal Is a Huge Win for Women’s Professional Sports," by Percy Allen (The Seattle Times, 2020).
  • "Sue Bird & Megan Rapinoe," (ESPN The Magazine Body Issue, 2018).
  • "Missed Shots at the Free-Throw Line: Analyzing the Determinants of Choking Under Pressure," by Mattie Toma (Journal of Sports Economics, 2015).

• EXTRAS:
  • "Marc Davis Can’t Stop Watching Basketball — But He Doesn’t Care Who Wins," by People I (Mostly) Admire (2021).
  • "The Hidden Side of Sports," series by Freakonomics Radio (2018-19).
  • "The True Story of the Gender Pay Gap," by Freakonomics Radio (2016).

Conrad Wolfram wants to transform the way we teach math — by taking advantage of computers. The creator of Computer-Based Maths convinced the Estonian government to give his radical curriculum a try — so why is the rest of the world so resistant?

SOURCE:

Conrad Wolfram, strategic director and European cofounder/C.E.O. of Wolfram Research, and founder of computerbasedmath.org.

RESOURCES:

"In California, a Math Problem: Does Data Science = Algebra II?" by Amy Harmon (The New York Times, 2023).
The Math(s) Fix: An Education Blueprint for the AI Age, by Conrad Wolfram (2020).
"The Movement to Modernize Math Class," by Yoree Koh (The Wall Street Journal, 2020).
"Math Rebels Invade Estonia With Computerized Education," by Klint Finley (Wired, 2013).
"Do Left-Handed People Really Die Young?" by Hannah Barnes (BBC News, 2013).
"Teaching Kids Real Math With Computers," by Conrad Wolfram (TED Talk, 2010).

EXTRAS:

"Bringing Data to Life," by People I (Mostly) Admire (2023).
"Steven Strogatz Thinks You Don’t Know What Math Is," by People I (Mostly) Admire (2023).
"Mathematician Sarah Hart on Why Numbers are Music to Our Ears," by People I (Mostly) Admire (2021).
"America’s Math Curriculum Doesn’t Add Up," by People I (Mostly) Admire (2021).

Ellen Langer is a psychologist at Harvard who studies the mind-body connection. She’s published some of the most remarkable scientific findings Steve has ever encountered. Can we really improve our physical health by changing our mind?

• SOURCE:
  • Ellen Langer, professor of psychology at Harvard University.

• RESOURCES:
  • Brave New Words: How AI Will Revolutionize Education (and Why That's a Good Thing), by Sal Khan (2024).
  • "F.D.A.’s Review of MDMA Cites Health Risks and Study Flaws," by Andrew Jacobs and Christina Jewett (The New York Times, 2024).
  • The Mindful Body: Thinking Our Way to Chronic Health, by Ellen Langer (2023).
  • "Physical Healing as a Function of Perceived Time," by Peter Aungle and Ellen Langer (Nature: Scientific Reports, 2023).
  • "Aging as a Mindset: A Study Protocol to Rejuvenate Older Adults With a Counterclockwise Psychological Intervention," by Francesco Pagnini, Cesare Cavalera, Ellen Langer, et al. (BMJ Open, 2019).
  • Counterclockwise: Mindful Health and the Power of Possibility, by Ellen Langer (2009).
  • "Mind-Set Matters: Exercise and the Placebo Effect," by Alia Crum and Ellen Langer (2007).
  • "The Effects of Choice and Enhanced Personal Responsibility for the Aged: A Field Experiment in an Institutional Setting," by Ellen Langer and Judith Rodin (Journal of Personality and Social Psychology, 1976).

• EXTRAS:
  • "The Future of Therapy Is Psychedelic," by People I (Mostly) Admire (2023).
  • "Extra: An Update on the Khan World School," by People I (Mostly) Admire (2023).
  • "Is This the Future of High School?" by People I (Mostly) Admire (2022).
  • "What It Takes to Know Everything," by People I (Mostly) Admire (2022).
  • "Sal Khan: 'If It Works for 15 Cousins, It Could Work for a Billion People,'" by People I (Mostly) Admire (2021).
  • "Greg Norman & Mark Broadie: Why Golf Beats an Orgasm and Why Data Beats Everything," by People I (Mostly) Admire (2021).
  • "Caverly Morgan: 'I Am Not This Voice. I Am Not This Narrative,'" by People I (Mostly) Admire (2020).
  • "Does 'As If' Thinking Really Work?" by No Stupid Questions (2020).
  • "Havana Wild Weekend," S28.E7 of The Simpsons (2016).

Author and YouTuber John Green thought his breakout bestseller wouldn’t be a commercial success, wrote 40,000 words for one sentence, and brought Steve to tears.

• SOURCE:
  • John Green, best-selling author and YouTube creator.

• RESOURCES:
  • "The Deadliest Infectious Disease Isn’t a Science Problem. It’s a Money Problem," by John Green (The Washington Post, 2024).
  • “Tuition Inflation Isn’t as Bad as You Think,” by Felix Salmon (Axios, 2022).
  • “Fast Facts: Expenditures,” by the National Center for Education Statistics (2022).
  • “Trends in College Pricing and Student Aid 2021,” by the College Board (2021).
  • “#37 John,” by Heavyweight (2021).
  • The Anthropocene Reviewed: Essays on a Human-Centered Planet, by John Green (2021).
  • “Scratch ‘n’ Sniff Stickers and the Indianapolis 500,” by The Anthropocene Reviewed Podcast (2019).
  • “How Joan of Arc Conquered Mark Twain,” by Ted Gioia (America: The Jesuit Review, 2018).
  • Turtles All the Way Down, by John Green (2017).
  • The Fault in Our Stars, film (2014).
  • The Fault in Our Stars, by John Green (2012).
  • Looking for Alaska, by John Green (2005).
  • All the King’s Men, by Robert Penn Warren and Noel Polk (1946).
  • Harvey, film (1950).
  • vlogbrothers, YouTube channel by John and Hank Green.
  • Crash Course, YouTube channel by John and Hank Green.

• EXTRAS:
  • “Peter Singer Isn’t a Saint, But He’s Better Than Steve Levitt,” by People I (Mostly) Admire (2022).
  • “Freakonomics Radio Goes Back To School,” series by Freakonomics Radio (2022).

Suleika Jaouad was diagnosed with cancer at 22. She made her illness the subject of a New York Times column and a memoir, Between Two Kingdoms. She and Steve talk about what it means to live with a potentially fatal illness, how to talk to people who've gone through a tragedy, and ways to encourage medical donations.

• SOURCE:
  • Suleika Jaouad, author.

• RESOURCES:
  • "The Art of Survival," by Jennifer Senior (The Atlantic, 2024).
  • American Symphony, film by Matthew Heineman (2023).
  • Between Two Kingdoms: A Memoir of a Life Interrupted, by Suleika Jaouad (2021).
  • "Max Ritvo, Poet Who Chronicled His Cancer Fight, Dies at 25," by John Schwartz (The New York Times, 2016).
  • “Life, Interrupted,” column by Suleika Jaouad (The New York Times, 2012-2015).
  • The Fault in Our Stars, by John Green (2012).
  • Bright-sided: How Positive Thinking Is Undermining America, by Barbara Ehrenreich (2009).
  • The Isolation Journals, newsletter by Suleika Jaouad.

• EXTRAS:
  • "John Green’s Reluctant Rocket Ship Ride," by People I (Mostly) Admire (2022).
  • "Does Death Have to Be a Death Sentence?" by People I (Mostly) Admire (2022).

Caroline Paul is a thrill-seeker and writer who is on a quest to encourage women to get outside and embrace adventure as they age. She and Steve talk about fighting fires, walking on airplane wings, and finding awe in birdwatching.

• SOURCE:
  • Caroline Paul, author and former firefighter.

• RESOURCES:
  • Tough Broad: From Boogie Boarding to Wing Walking ― How Outdoor Adventure Improves Our Lives as We Age, by Caroline Paul (2024).
  • "FAA Halts Sequim Wing-Walking Flights, Revokes Owner’s Pilot License," by Dominic Gates (The Seattle Times, 2024).
  • "How a Bit of Awe Can Improve Your Health," by Hope Reese (The New York Times, 2023).
  • The Gutsy Girl: Escapades for Your Life of Epic Adventure, by Caroline Paul (2016).
  • "Why Do We Teach Girls That It’s Cute to Be Scared?" by Caroline Paul (The New York Times, 2016).
  • "What if Age Is Nothing but a Mind-Set?" by Bruce Grierson (The New York Times Magazine, 2014).
  • Lost Cat: A True Story of Love, Desperation, and GPS Technology, by Caroline Paul (2013).
  • "The Cognitive Benefits of Interacting With Nature," by Marc G. Berman, John Jonides, and Stephen Kaplan (Psychological Science, 2008).
  • "Longevity Increased by Positive Self-Perceptions of Aging," by Becca R. Levy, Martin D. Slade, Suzanne R. Kunkel, and Stanislav V. Kasl (Journal of Personality and Social Psychology, 2002).
  • Fighting Fire, by Caroline Paul (1998).

• EXTRAS:
  • "Is Fear Running Your Life?" by No Stupid Questions (2024).
  • "Arnold Schwarzenegger Has Some Advice for You," by People I (Mostly) Admire (2024).
  • "Should You Spend More Time in Nature?" by No Stupid Questions (2023).
  • "Steven Pinker: 'I Manage My Controversy Portfolio Carefully,'" by People I (Mostly) Admire (2020).