Final answer:
The female pelvis differs from the male pelvis with its lighter bones, wider structure, greater subpubic angle, rounded pelvic inlet, and shallower cavity, which are all adaptations for childbirth. Option (a) is the correct answer to the question.
Step-by-step explanation:
The major differences between the male pelvis and female pelvis that permit childbirth in females are related to their structure and shape to facilitate the birthing process. The correct option for the question is (a) The female pelvis is wider, shallower, and has a larger pelvic inlet and outlet compared to the male pelvis. The female pelvis features lighter and thinner bones, a wider pelvic brim with a round or oval shape, and a broader subpubic angle greater than 80 degrees. Moreover, the sciatic notch is broader, and the ischial tuberosities are farther apart, expanding the pelvic outlet to accommodate the passage of a baby during childbirth. In contrast, the male pelvis is characterized by thicker and heavier bones, a narrower and deeper shape, and a subpubic angle of less than 70 degrees.
The adaptations of the female pelvis, including a wider sacrum that is less curved and a lesser pelvic cavity that is more shallow, are significant evolutionary changes that have enabled successful childbirth. These anatomic characteristics of the pelvis are the most reliable for determining the sex of skeletal remains. Since childbirth is not a function of the male pelvis, it is structured to support a stronger physique and provide attachment for heavier muscles.