About this episode
We’re back with an episode from the Radiolab archive. Horseshoe crabs have been around for a long time. They outlived the dinosaurs, survived all mass extinctions and witnessed the sprouting of the Earth’s first trees. The secret to their longevity? Their baby blue blood. Which has been saving both their lives and ours. Lulu and Radiolab co-host, Latif Nasser, head to one of these bleeding facilities to learn how horseshoe crab blood became indispensable for modern medicine. And how this vampirish relationship humans have with the crabs might also be crucial to keeping them alive. Terrestrials will be back in September 2025 with all new episodes airing every other week! SIgn up for our newsletter here and follow us on Instagram @terrestrialspodcast for updates. If you want to learn more about how miraculous horseshoe crabs are, check out: Alexis Madrigal, "The Blood Harvest" in The Atlantic, and Sarah Zhang's recent follow up in The Atlantic, "The Last Days of the Blue Blood Harvest" Deborah Cramer, The Narrow Edge Deborah Cramer, "Inside the Biomedical Revolution to Save Horseshoe Crabs" in Audubon Magazine Richard Fortey, Horseshoe Crabs and Velvet Worms Ian Frazier, "Blue Bloods" in The New Yorker Lulu Miller's short story, "Me and Jane" in Catapult Magazine Jerry Gault, "The Most Noble Fishing There Is" in Charles River's Eureka Magazine Glenn Gauvry's horseshoe crab research database HEY GROWN-UPS! Love the show? Leave us a ⭐⭐⭐⭐⭐ rating and review on your podcast app—it helps curious listeners find us! We want to hear from you! Share your thoughts about Terrestrials with us . Subscribe to our weekly newsletter for bite-sized essays, activities, and ways to connect with the show. Follow us on YouTube , Instagram , and TikTok for behind-the-scenes extras and more. Listen to original music from Terrestrials on Spotify , Apple Music , or our music page . Got a badgering question for the team? Email us at terrestrialspodcast@wnyc.org or submit a voice memo with your name, age, and your question using this form ! Terrestrials is made possible in part by listeners like you. Support the show by joining Radiolab’s membership program, The Lab—and we’ll send you a special thank-you gift from our team!