Final answer:
To determine an individual's age, scientists examine the pubic symphysis, iliac auricular surface, and cranial suture closure in adults, and rely on epiphyseal fusion and dental indicators in those under twenty years old.
Step-by-step explanation:
Scientists examine specific parts of the skeleton to help determine the age of an individual. Three principal parts analyzed for this purpose in adults are the pubic symphysis, the iliac auricular surface, and the evidence of cranial suture closure. In individuals younger than twenty years, epiphyseal fusion, dental development, and dental eruption are critical indicators used for age estimation.