It is a bone consisting of the ilium (upward), ischium (downward and backward), and pubis (downward and forward) bones. The ischium and pubis bones fuse around the age of 7, while the ilium bone fuses with them around the age of 15 or 16. These bones connect with their bodies to form the acetabulum (ilium-2/5 of the acetabulum, pubis-1/5 of the acetabulum, and ischium-2/5 of the acetabulum). On the basis of the shape of the pubic, iliac and ischial bones, it is possible to identify both the sex and age of an individual. Generally speaking, the female pelvis is low and wide, with the dimensions of the smaller pelvis clearly marked. The male pelvis is high, with less of a lumen in the lesser pelvis.