The human female pelvis has long been viewed as a compromised structure, suggesting it is not best designed for anything. The dominant evolutionary model of trade-offs for the female pelvis is the Obstetrical Dilemma Hypothesis (ODH), which posits that a narrow pelvis is ideal for bipedal locomotion, but must be traded off against the need for a broad pelvic obstetric canal to birth large-brained (and broad-shouldered) human babies. Males of the species need only accommodate the first pressure - locomotion. This hypothesis has underlain how we think about the human female pelvis for decades, at least since Washburn first articulated it in a single paragraph in 1951 in Scientific American Magazine. Despite its humble beginnings, the hypothesis has had an enormous impact on how we view female-male differences, grounding the perspective that females are not as fast or efficient at walking or running, therefore not as athletic as males, as well as the notion that human childbirth is fundamentally and uniquely risky, and therefore in need of medicalisation and something to be feared. 

Despite challenges to the supremacy of the obstetrics vs. locomotion trade-off in recent years, including the recognition of the role of additional selective factors and neutral evolutionary processes in shaping hominin pelvic evolution, as well as the recognition that obstetric challenges pervade the mammalian lineage, not just our own, the Obstetrical Dilemma narrative still shapes how we think about the female pelvis and its functioning. The language of a “dilemma” is uniquely applied to the human female pelvis, and that part of the myth is particularly problematic. This talk examines the mythos of the ODH and argues that the logos of the human pelvis and childbirth is complex and less unique within the mammalian order than we might often believe.

About the Speaker
Dr. Helen Kurki is a Professor in the Department of Anthropology at the University of Victoria. Her research focuses on human skeletal variation and the factors that shape it.