Where do animals come from? That's something people have been trying to explain for thousands of years. And for a while, scientists and philosophers believed that any ol' person could create creatures if they just had the right recipe. A touch of sand, maybe a drop of blood and POOF: you could create life. That idea was believed to be true for generations until one brave scientist decided to look more closely at an unlikely bug and change the course of science forever. Lulu calls up our biology correspondent, Dr. Avir Mitra, to solve this ancient mystery.

Terrestrials was created by Lulu Miller with WNYC. This episode was produced by Ana González and Alan Goffinski, with sound design by Mira Burt-Wintonick. Sarah Sandbach is our Executive Producer. Our team also includes Tanya Chawla and Joe Plourde. Factchecking by Diane Kelly.

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

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