One important study that all Bio anthropologists use is the study of bones. Or the fancier term osteology. Osteology studies the growth, development, and variation in the human skeletal system. It tries also to explain anomalies, whether different variation is cultural or genetic, and observable pathologies. Most physical anthropologists need to use osteology one way or another. For a forensic anthropologist, it is there prime tool used. Using forensic anthropologists, I will show you what physical anthropologist think when looking at bones in the perspective of forensics.
If you never heard of a forensic anthropologist, no worries there are only about two hundred anthropologists that work full-time time in forensics! Most are physical anthropologists that work in academia or research facility that get called for their service from the coroner to analyze and observe the human remains. One of the main reasons for this is the need for forensic anthropologists is rare. Most human remains are not so decomposed to hold little other evidence or a form of identification for the remains. But because their services are rare does not mean they are irrelevant. They help put names identity to the remains of homicides, genocides, and mass grave victims.
Forensic anthropology is a specialized branch of physical anthropology that become expert witnesses ,who is a specialized informer to a case, that give testimony in court. And they analyze skeletal remains to determine the age, sex, stature, ancestry, and trauma. To apply that to their physiological age, based on skeletal observation, and chronological age, the actual age from date of birth, for further evidence to get an identification.
There are three important questions that need to be answered to determine forensic significance. Even if they sound dumb, based on the varies conditions bones can be collected these questions are essential.
- Are the remains Bone?
- Are the remains Human? If any remains have tissue on them or are mostly in one spot it can be easy to identify. But if they are sparse and spaced apart it can be difficult. One way to tell is to look at the microscopic structure of the bones.
- Are the remains ancient, historic, or modern? Can usually tell based on context of their surroundings, material found with the remains, or the remains themselves. If not they are not modern, they are not of forensic significance.
The techniques and knowledge used to solve murder cases are very like what other physical anthropologist use to examine ancient or historic remains.
The skull and the pelvis are the most used to determine sex. The pelvis is the easiest and most reliable to tell if they belong to a female or male. Women’s pelvis one important function that male pelvises don’t and that to give birth. And because we are bipedal and are born with fairly large heads the female pelvis had to go through some evolutionary change to allow the birth and development of children in their womb. So female pelvises are generally wider with an obtuse pubic angel. The sacrum bone is tilted back so it’s not in the way of the baby. And a very much bigger pelvic outlet to fit birth canal.
Male skulls are generally larger and more square than female skulls. And female skulls are more gracile and smoother along the bones surfaces. Male suborbital ridges (brow ridge) are a lot larger and ruff. The mental protuberance (chin) is usually more square and thicker in men. Mastoid process is thicker and larger in men. And male skulls have an occipital protuberance at the back of the skull.
Even though race has been debunked scientifically and most biologists and physical anthropologists don’t believe it has any scientific standing, it still plays a role in our society and politics. So forensic anthropologists are obligated to designate a race to the human remains to help put a potential identification.
But what it really comes down to is phenotype traits that are in high frequency in certain populations based on ancestry. Such as the shape of the head, nose, face, and proportions of upper and lower limbs. It comes down to ancestry and morphological traits by climate, ecology or cultural factors. And the most morphological differences are in the Skull.
The traditional categories are selections for three ancestors called Negroid, Mongolid, and Caucasoid. Just because there are these three categories doesn’t mean the traits are inherently persistent in these overgeneralized geographic groups.
Here are some general distinctions for each category
Caucasoid skulls: generally, have very narrow features. Like a narrow face, narrow nasal opening, and nasal bones above the opening. And a slight overbite.
Negroid Skulls : generally, have a round forehead, wide nasal opening, also wide nasal bones. And a slight to extreme overbite.
Mongaloid Skulls: have a flat face, no overbite, and cheekbones flare out more. Also common to have shoveling behind the incisors.
There are multiple indicators of aging and age. Two of the most commonly known are clues in human dentition and epiphyseal fusion of long bones.
We go through two set of teeth in our life. The primary or deciduous teeth are more commonly known as baby teeth. And our secondary or permanent teeth. The nice thing about teeth is they erupt at predictable rates. And can get an accurate age before the age of 25.
There are two main pars of the bone, the shaft and the epiphyses or the cap at the end. During paternal development, epiphyseal are separate and are joined by cartilage to the shaft. Then at different times in development the bones will ossify (make bone) and replace the cartilage. And eventually unite completely.
Use the regression formula to tell the stature of the remains. For this it is important to know the sex and ancestry of the remains for it is part of the formula to assess the stature. By measuring the stature, you need to measure the long bones like the femur or tibia by using a osteometric table.
More information on the remains is to look at the bones that have muscle markings. For this is the area of the bone where the bone attaches to muscles through ligaments. They can help determine whether a person is athletic or not, their handedness, and possible job they had.
If you would like more information on forensic anthropology, then i suggest to take a look at the following book and websites.
The Bone Detectives by Donna M. Jackson- a short, but very informative book about forensic and physical anthropology.
Flesh and Bone by Myriam Nafte- a great and inexpensive book that real anthropologist use!