The pelvic bones, also known as the pelvis, form the base of the spine and support the weight of the upper body when sitting or standing. They consist of three main parts: the ilium, ischium, and pubis, which fuse together in adulthood. The pelvis also protects vital organs in the lower abdomen, including the bladder and reproductive organs. In addition to providing structural support, the pelvic bones play a crucial role in movement. They connect the spine to the femurs (thigh bones) and facilitate walking, running, and other activities. The shape and size of the pelvis can vary between individuals and is often different between males and females.