Phys.org

Neanderthal hips challenge long-standing hypothesis of a trade-off between childbirth and bipedal walking

The most prominent difference between human male and female skeletons is the pelvis, which anthropologists often use to determine the sex of ancient remains. Scientists have long believed the human pelvis evolved mainly as a compromise between walking on two legs and giving birth to large-brained babies. This idea is known as the Obstetrical Dilemma Hypothesis.