Covariation between human pelvis shape, stature, and head size alleviates the obstetric dilemma.

ABSTRACT: Compared with other primates, childbirth is remarkably difficult in humans because the head of a human neonate is large relative to the birth-relevant dimensions of the maternal pelvis. It seems puzzling that females have not evolved wider pelvises despite the high maternal mortality and morbidity risk connected to childbirth. Despite this seeming lack of change in average pelvic morphology, we show that humans have evolved a complex link between pelvis shape, stature, and head circumference that was not recognized before. The identified covariance patterns contribute to ameliorate the "obstetric dilemma." Females with a large head, who are likely to give birth to neonates with a large head, possess birth canals that are shaped to better accommodate large-headed neonates. Short females wit

SUBMITTER: Fischer B 

PROVIDER: S-EPMC4426453 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature