"I know it sounds weird, but I felt an almost father-child relationship with this organism that was growing in my body," the entomologist says.

Stream "NOVA Wonders: What's Living in You?" online or on the PBS app now at: pbs.org/wgbh/nova/wonders/#living-in-you

Digital Producer Michael Rivera

WHAT'S LIVING IN YOU? Written, Produced, and Directed by Peter Yost

© WGBH Educational Foundation 2018