Podcast:Unexplainable Published On: Mon Jun 01 2026 Description: Fetuses leave cells behind in their parents' bodies, where they braid themselves into tissues, and remain, for years. What are they doing in there? (Originally aired in 2023) Guests: Amy Boddy, Associate Professor of Anthropology at the University of California, Santa Barbara; Lee Nelson, Professor Emeritus at the Fred Hutch Cancer Center For show transcripts, go to vox.com/unxtranscripts For more, go to vox.com/unexplainable And please email us! unexplainable@vox.com We read every email. Support Unexplainable (and get ad-free episodes) by becoming a Vox Member today: vox.com/members Thank you! Learn more about your ad choices. Visit podcastchoices.com/adchoices