Origin Stories

Episode 54: The Obstetrical Dilemma

Origin Stories

Show Notes

The widely-held idea known as the "obstetrical dilemma" is a hypothesis that explains why babies are so helpless, and why childbirth is so difficult for humans compared to other animals. The obstetrical dilemma suggests that babies are born early so their big brains can fit through the mother's pelvis, which can't get any wider due to our method of bipedal locomotion. This problem, the idea says, is solved by an evolutionary tradeoff that increases risks to pregnant mothers who must struggle to birth bigger and bigger-brained babies through narrow birth canals. On this episode, Leakey Foundation grantees Dr. Holly Dunsworth and Dr. Anna Warrener describe their search for the evidence behind the obstetrical dilemma and they discuss the importance of the stories we tell about our bodies. Send us your questions! Have a question about human evolution? Something you've always wondered about? We will find a scientist to answer it on a special episode of Origin Stories! There are three ways to submit your question: Leave a voicemail at (707) 788-8582 Visit speakpipe.com/originstories and leave a message Record a voice memo on your phone and email it to us at [email protected] Links The Mermaid's Tale A Most Interesting Problem There is no 'obstetrical dilemma': towards a braver medicine with fewer chilbirth interventions Metabolic hypothesis for human altriciality A Wider Pelvis Does Not Increase Locomotor Cost in Humans, with Implications for the Evolution of Childbirth The obstetrical dilemma hypothesis: there's life in the old dog yet YouTube - Close up video of chimp childbirth The Leakey Foundation Origin Stories is a project of The Leakey Foundation, a nonprofit organization dedicated to funding human origins research and outreach. All donations to support the podcast will be quadruple-matched thanks to Jeanne Newman and the Ann and Gordon Getty Foundation. Visit leakeyfoundation.org/donate and use the notes field let us know your donation is in support of Origin Stories. Thanks Thanks to Lynn and Larry Schafran for sponsoring this episode. We are grateful for their support of The Leakey Foundation and our educational programs. Lunch Break Science Lunch Break Science is The Leakey Foundation's web series featuring short talks and interviews with Leakey Foundation grantees. Episodes stream live on the first and third Thursdays of every month. Sign up for event reminders and watch past episodes at leakeyfoundation.org/live

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