Skeletal traits on the skull and pelvis can also help anthropologists determine whether an adult was male or female, and how old he or she was at the time of death. Conversely, it is extremely difficult to assess the sex of children since they have not reached puberty, when sexual characteristics become apparent. Some skeletal traits associated with sex include the widening of the female pelvic opening to support childbirth, or the roughening of the male occipital bone on the skull, usually associated with large muscle attachments. Before puberty, these sexual traits have not yet surfaced. Bones also contain evidence pertaining to nutrition, disease, and trauma.
Skeletal characteristics can provide clues to the individual's life history.
These and numerous other questions can be answered from the record left on the skeleton of an individual. For instance, the remodeling or healing of bone as a result of a fracture or other trauma can be observed. The degenerative disease called osteoarthritis brings about telltale changes which remain as evidence in the skeleton. Normally, there is cartilage between bones which separates them. However, in the case of osteoarthritis, the cartilage has degenerated, and the bones rub against each other.