ReviewAmerican journal of human biology : the official journal of the Human Biology Council2019
Humans as inverted bats: A comparative approach to the obstetric conundrum.
Review in American journal of human biology : the official journal of the Human Biology Council, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 23 papers.
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Who cites it
23 citing papers in PubMed, 55 citations in OpenAlex.
- Humans are not unique: difficult birth is common in placental mammals.Biological reviews of the Cambridge Philosophical Society · 2026Review
- Conflict, Constraint, Cooperation, and Allocation: A Plural Evolutionary Architecture for Human Reproductive Paradoxes.American journal of biological anthropology · 2026Article
- Comparative primate analysis shows that humans are not unique in having a tight cephalopelvic fit at birth.Nature ecology & evolution · 2026Article
- Sex determination using image processing reveals elliptical features of the female pelvic inlet.Scientific reports · 2025Article
- Variation in Pubic Symphysis Fusion Across Primates: Implications for Obstetric Adaptation.American journal of biological anthropology · 2025Article
- The mouse pubic symphysis: a narrative review.Frontiers in physiology · 2025Review
- Gradual exacerbation of obstetric constraints during hominoid evolution implied by re-evaluation of cephalopelvic fit in chimpanzees.Nature ecology & evolution · 2024Article
- No birth-associated maternal mortality in Japanese macaques (Proceedings of the National Academy of Sciences of the United States of America · 2024Article
- Scrutinizing microbiome determinism: why deterministic hypotheses about the microbiome are conceptually ungrounded.History and philosophy of the life sciences · 2024Article
- The evolution of human altriciality and brain development in comparative context.Nature ecology & evolution · 2024Article
- There is an obstetrical dilemma: Misconceptions about the evolution of human childbirth and pelvic form.American journal of biological anthropology · 2023Review
- Article
- Cleft Palate Syndrome in the Endangered Spectacled Flying Fox (Veterinary sciences · 2023Article
- Take it to the limit: The limitations of energetic explanations for birth timing in humans.Evolution, medicine, and public health · 2023Review
- Squatting, pelvic morphology and a reconsideration of childbirth difficulties.Evolution, medicine, and public health · 2022Article
- The evolution of pelvic canal shape and rotational birth in humans.BMC biology · 2021Article
- The obstetrical dilemma hypothesis: there's life in the old dog yet.Biological reviews of the Cambridge Philosophical Society · 2021Article
- Sex differences in the pelvis did not evolve de novo in modern humans.Nature ecology & evolution · 2021Article
- Biomechanical trade-offs in the pelvic floor constrain the evolution of the human birth canal.Proceedings of the National Academy of Sciences of the United States of America · 2021Article
- Article
Corrections and comments
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Authors and funding
6 authors at 5 institutions in 2 countries.
Funding
Abstract
objectivesThe narrow human birth canal evolved in response to multiple opposing selective forces on the pelvis. These factors cannot be sufficiently disentangled in humans because of the limited range of relevant variation. Here, we outline a comparative strategy to study the evolution of human childbirth and to test existing hypotheses in primates and other mammals.
methodsWe combined a literature review with comparative analyses of neonatal and female body and brain mass, using three existing datasets. We also present images of bony pelves of a diverse sample of taxa.
resultsBats, certain non-human primates, seals, and most ungulates, including whales, have much larger relative neonatal masses than humans, and they all differ in their anatomical adaptations for childbirth. Bats, as a group, are particularly interesting in this context as they give birth to the relatively largest neonates, and their pelvis is highly dimorphic: Whereas males have a fused symphysis, a ligament bridges a large pubic gap in females. The resulting strong demands on the widened and vulnerable pelvic floor likely are relaxed by roosting head-down.
conclusionsParturition has constituted a strong selective force in many non-human placentals. We illustrated how the demands on pelvic morphology resulting from locomotion, pelvic floor stability, childbirth, and perhaps also erectile function in males have been traded off differently in mammals, depending on their locomotion and environment. Exploiting the power of a comparative approach, we present new hypotheses and research directions for resolving the obstetric conundrum in humans.
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.