In case of any civil or criminal acts, physical evidence present on the field is collected, recovered, and analyzed in laboratory which includes the analysis of human skeletal remains. Forensic anthropologists analyze the victims to determine if it was an accidental deaths, homicide, mass fatalities or natural deaths.
Age and Gender Identification
By carefully examining the length of the bones of a deceased person, they can identify the age of the victim. The caps on the end of long bones fuse completely with the bones (extent of fusion of the epiphysis) after the age of 20. Similarly, epiphysis on the sternal end of clavicle fuses around the age of 30. In elderly, the sternal end of the fourth rib starts changing. Depth of the pitting of ribs helps in identifying an accurate age of the victim. For the victims who are above 30 years of age, signs of deterioration are visible in their bodies. Their bones become more porous, less dense. Work-related injuries and little arthritic projections can be seen in their bones. The size of the skull and pubis bone indicates the gender of the deceased person. Pubic bone is elongated in women which allows them for childbirth. However, the head of the women are comparatively smaller than men. The probability of the sex determination from the skull is 85 to 90%. Identifying the race is a complex issue because of the increasing population leading to a diverse multiracial citizenry. By the distinctive characteristics of the skeleton, black and white Asian or native Americans are identified regardless of their skin color. The race of skeletal remains is determined by the measurement and observation of both postcranial skeleton and skull. Facial region is considered as the most diagnostic for racial attribution. Nonmetric racial features of the skull include such features as overall shape of the skull, shape of the orbit, shape of the nasal region, shape of the lower jaw, degree of protrusion of the jaw or prognathism and certain other features of the teeth. Cranial and facial measurements are used as a diagnostic for determining race. Stature is determined by the measurement of femur (thigh bone) which is the longest bone in the body. The results are combined with the measurement of tibia or lower shinbone for the estimation of height.
Trauma and Surgeries
Other factors can also be determined by forensic experts by the application of their knowledge, skillset, and experience. Traumas are identified and classified into three categories i.e. antemortem trauma which includes all the injuries sustained during life and an evidence of healing is observable. Perimortem trauma are all the injuries sustained at the time of death which is usually a cause of death. Post-mortem trauma are those injuries which are sustained after death because of environmental factors. If the victim had been ill or malnourished during childhood, fine horizontal grooves on the front teeth (incisor) of the victim are observable. If the victim had a history of domestic violence, healing fractures of different stages can be observed on the victim’s hands, face, and ribs. Orthopedic implants in the knee are present as a result of sport related injury. Identifying the cause of death is not the only task of forensic anthropologist but they are also trained to evaluate and recognize how the environmental conditions alter the appearance and composition of bones over a period of time since death. For example, tiny parallel grooves and conical depression can be inferred as knife wounds which could be a result of a tooth mark from a rodent or a carnivore. Upper body strength is indicated if the growth of musculature is affected in the specific ways. Several injuries in the fingers indicate heavy manual labor and certain anomalies in teeth indicate that the food eaten by the deceased was mixed with ground stone.