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Allometry and sexual dimorphism in the human pelvis

Sexual dimorphism in the human pelvis has evolved in response to several jointly acting selection regimes that result from the pelvis’ multiple roles in locomotion and childbirth, among others. Because human males are, on average, taller than …

Reply to Grossman: The role of natural selection for the increase of Caesarean section rates

Recently, we presented the “cliff-edge model” (1) to explain why natural selection has not reduced the high rates of fetopelvic disproportion (FPD) in childbirth. This evolutionary model predicts that birth-relevant anatomical dimensions have changed …

Cliff-edge model of obstetric selection in humans

The strikingly high incidence of obstructed labor due to the disproportion of fetal size and the mother’s pelvic dimensions has puzzled evolutionary scientists for decades. Here we propose that these high rates are a direct consequence of the …

Adult pelvic shape change is an evolutionary side effect

In their interesting article, Huseynov et al. (1) propose the “developmental obstetric dilemma (DOD) hypothesis,” which posits that human pelvic morphology reflects the changing obstetric needs during a female’s lifetime. In particular, the authors …

Lateral plate number in low‐plated threespine stickleback - a study of plasticity and heritability

Reply to Underdown and Oppenheimer: Roles of selection, plasticity, and genetics in the integration of human pelvis shape and head size

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

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 …

Strong and parallel salinity‐induced phenotypic plasticity in one generation of threespine stickleback

Phenotypic plasticity is a major factor contributing to variation of organisms in nature, yet its evolutionary significance is insufficiently understood. One example system where plasticity might have played an important role in an adaptive radiation …

The Evolution of Age-Dependent Plasticity

When organisms encounter environments that are heterogeneous in time, phenotypic plasticity is often favored by selection. The degree of such plasticity can vary during an organism’s lifetime, but the factors promoting differential plastic responses …

A noninvasive method to determine fat content in small fish based on swim bladder size estimation