how to distinguish a male and a female skeleton based on the structure of the pelvis? explain why this is so

Answer: Like the skull, the pelvis is highly useful for determining a skeleton's biological sex. A wide pelvis is beneficial for child birth, however a narrow pelvis is beneficial for locomotion when walking upright. These conflicting demands are often termed the obstetrical dilemma.

The female pelvis has evolved to its maximum width for childbirth-a wider pelvis would make women unable to walk. In contrast, human male pelvis are not constrained by the need to give birth and therefore are optimized for bipedal locomotion.