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Ancestry is More Than Skin Deep

10/25/2015

When you look at a person, you can get an idea of where they're from by the look of their skin, their eyes, even of their hair. But what happens when their skin is gone, could you still? From the skulls that are in the media, it seems safe to say that all male skulls are the same along with female skulls. Now, if you remember from my blog titled “Week 5” (http://anthropologicalconcepts.weebly.com/blog/week-5), the appearance of the skull can have lots to do how your outer face can look like. In this weeks blog I will discuss how each ethnicity or ancestry's have very different skulls. “The groups are African, European, Asian, and Oceanic. This is an imperfect classification system, but it is useful in the broad base of assigning identity to an individual.” I will be using terms that might be unfamiliar to you, so below I have included a photo marked with the areas I will address.

Below we have a photo of an African skull. African refers to individuals descendant from Saharan and sub-Saharan Africa. From the side the noticable African acestry is marked by a long crainal shape, and moderate to strong prognathism. Also from the side, they have a flat anterior nasal spine and a “Quonset-hut like nasal root morphology, which means that it is almost semi circular in cross section.” From the front you can see they have rectangular orbits and a wide inter-orbiral distance, along with a broad nasal aperture. In addition to these that you can see from the side and from the front, there is one that you can notice from both views; the brow ridges. They have a “mild to moderate development of the brow ridges with a moderate glabella.”

Next we have European (image below). European refers to individuals descendant from the European continent, the Indian subcontinent, North Africa, and the Middle East. For European ancesty they have a rounded cranial shape. You can immediately notice that they have a prominent nose from how far their nasal root is (this type of nasal root is usually called “steepled.”). Other features of the nose is their nasal aperture is narrow, and the anterior nasal spine is prominent along with the chin. The front shows they have angular orbits, and a narrow inter-orbital distance. For the brow ridges and glabella, they would have moderate to strong brow ridges, but with a depressed glabella.

With the Asian skull (image below), which refers to individuals descendant from Central or East Asia, First Nation Americans, Inuits and some groups in East Russia, it looks very similar to the European because of the rounded cranial shape, but they could not be more different. The face is wider and the major difference, I think, is in the nose. Unlike the European steepled nose, Asian ancesty has a tented nasal root, with a flat anterior nasal spine, and a moderate nasal aperture. For the eyes, they are classified as having a round orbital shape with a moderate inter-orbital distance. And unlike both the African and European ancestry, the Asian ancestry has a “faint or absent brow ridges and a moderately prominent glabella.”

Lastly we have a skull of Oceanic ancestry (image below). Oceanic refers to individuals descendant from First Nation inhabitants of the South Pacific Islands, New Zealand, and Australia. This skull looks nothing like the other ones, so it could not be mistaken for African, European, or Asian ancesty. They have a high and short cranial shape with a mild to moderate. The nasal root looks similar to that of European as it is steepled, but the anterior nasal spine is flat, like the African, and a moderate nasal aperture, like the Asian. Now with the eyes, they have a rectangular orbit shape with a wide inter-orbital distance. And unlike the skulls I addressed earlier, those of Oceanic ancestry will most likely have a well-developed brow ridges with a prominent glabella, and finally, “a rocker bottom jaw with a rounded mandibular margin.”

Now that you have seen how much ancestry can take effect with, not only on how our families does things, but also how we look, is it not silly to have believed that the only difference lies in if we are male or female. I have to admit, I was amoung the silly. It is lucky that physical/forensic anthropologists have made the distinctions because who knows how much we have traveled to difference places, and if a skeleton with Asian ancestry is found in Africa, it can be assumed that they were a tourist or the like.
Please feel free to comment on what you thought of the blog, or other physical anthropological subjects you would like me to cover.

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Week 6

10/18/2015

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This is the end of the last week of my Identifying the Dead class, and I have to say, it ended with a bang. It was so exciting to throw theories around who was the perpetrator and why. In the beginning of this week we learned who the victim was and towards the end who murdered her. Now if you read my post last week, I included the missing poster I made, and the victim looked almost exactly how the professional's missing poster looked like. But just because the victim looked like the official missing poster, does not mean the identification is over. What I mean by this is there is more work to be done.
Early in the class we learned about three primary identifiers; which are DNA, fingerprints, and dentition (teeth). Our victim was all bone and had been dead for five years, so DNA and fingerprints were not available. What as left was dentition. Even thought we all have teeth, just like we all have fingerprints, our teeth are distinctive down to the individual level. From cavities, fillings, missing teeth, the state of the 3rd molar (wisdom tooth), are all distinctive. For example, all adult humans have 32 teeth, I, who had braces and had to get teeth pulled, have 28. With our victim she had very distinctive cavities, and some of her 3rd molars were just erupting, and had a tooth missing, but this was most likely postmortem because there is no evidence of healing. The images below show what the dental chart of the victim (left), and the dental chart which was prepared by the dentist of the likely victim (right).

The rest of the class was with updates and news about the perpetrator. The perpetrator wrote a diary of the details of the murder, which we were given access to at the end of the class. If you enjoyed these past 6 weeks of me recounting this class, or are interested in taking this class, they are having it again next year: https://www.futurelearn.com/courses/identifying-the-dead. It really is great fun. The last section of this week was truly saddening, because...it is over now. But my appetite is more than whet now.
Please feel free to comment on what you thought of the blog, or other physical anthropological subjects you would like me to cover now that the weeks are done.

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Week 5

10/11/2015

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This week was on a topic that I was sparsely familiar with but not to the extent to be completely comfortable handling this week without the guidance of the teachers. The topic I am referring to is that of facial reconstruction. This needs to happen when a dead body is found without a face. Our body is all bones, and I must say, I was amazed by all that the skull can tell about the face. The first thing that is done is to scan the skull into a computer screen. Reason for this is that it lessens the risk of damaging the actual skull. Now the skull is classified into two categories (image below); “brachycephaly means wide and short, and dolichocephaly means narrow and long.” The skull is then compared to others to describe if the face is narrow or wide, if their cranium is large or small, and the shape of the chin (wide and square, rounded, or small and pointed).

The next thing the skull can tell us, is, of course, how far apart the eyes were. But there is something I did not know it could; the shape of the eyes. What is more the shape of the actual orbit (eye socket) can tell if the eye was bulging or portrusive or sunken. Not only can the skull tell about the eyes, but also about the victims eyebrows. If they have a brow ridge the eyebrows are more likely to be pushed down in the middle, and for the opposite, higher and more rounded. Another thing the orbits can tell about the face are where the corner of your eye is. They do this by using a bump on the outer corner of the eye called Whitnall's tubercle, this is where a ligament is tethered; this bump can be felt even in life. This ligament goes from that bone to another small one called the anterior lacrimal crest. (“This is where your tear duct connects your eye to your nose, and explains why your nose runs when you cry”) Because of these it can be quite precisely determined where the corner of the eyes are.
Next up is the nose. Most of your nose is fat, muscle, and cartilage. The bone that is linked to the shape of your nose is called the nasal aperture (image below). Now the length of the nose, depends on the projection and shape of the nasal bones at the bridge of the nose. Something that really took me by surprise was that they can even tell the shape of the nasal tip by these bones. There is even a way to tell if the nose was downturned, upturned, or straight. They do this by looking at the anterior nasal spine. For all of these traits of the nose they, again, need to compare it to other skulls.

Even the shape of the lips can be told by the skull. By this I mean the teeth and the size of the palate (bone behind the top teeth that separates your nose from your mouth). With this, a wider palate means a wider mouth and so on. And with the teeth, larger generally means large lips. When certain factors are taken into account, they can even tell if the lip shape was that of a cupid's bow. The way they can tell this is if the upper incisors in the middle are noticeably larger than the other front teeth.
From there I learned something that left my mouth agape, because it just proves how much information our skulls can say about us. I am sure that you have seen ears of every size, sticking out, or stuck to the head, the reason for these differences all have to with, you guessed it, the skull. Below your ears is something called the mastoid process, but in the skull, the mastoid process is below but behind the ear canal. The thicker it is, or the more it stands out, the more the ears will stand out (image below).
Needless to say, this week was very exciting. It is so...amazing that every part of our face has to do with how our skull is. As for next week, I am very excited because the identity of our victim (my missing poster below) is revealed and we make a stab at identifying the perpetrator. Even though I am excited, I am saddened because this is the last week of this class.
Please feel free to comment on what you thought of the blog, or other physical anthropological subjects you would like me to cover after next week is done.

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Week 4

10/4/2015

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This week had more hands on activities for the class. One of them was to look over the victim profile and deduce from the skeleton if they were female or male. Now, in a previous blog I covered sexing: http://anthropologicalconcepts.weebly.com/blog/male-or-female. But we covered something that I have been wanting to speak of, and that something is aging. Before I have covered the aging process and what the human body goes through as it gets older, but this type of aging happens after death.
     If the victim still has skin and clothes, they can profile and get a photo out to the public, and most likely will get someone who knows them. But what happens when all you have are bones? There are 3 bones that forensic anthropologists rely on when aging a body. These are the skull, the clavicle, the pubis, and the sternal end of the 4th rib.
     For the skull, they look for the joints called cranial sutures. What these are are the areas of the skull that have joined together. The more open the sutures, the younger the victim. These sutures have a time table that forensic anthropologist can estimate how old a victim was. These sutures do not close all the way til about the age of 20 or 21. Now just because they close at that age does not mean it ends there. As they age, the sutures begin to fuse. The less the fusion, the younger the victim.
  The clavicle (collar bone), aging has to with the fusion. Certain bones have several parts until we reach adult hood. We go from 300 as babies to 206 as adults. Now just because many of our bones have certain fusing timetables, forensic anthropologists use the clavicle because this one is the last to fuse to the main shaft. If the clavicle has no flaking on the surface of the bone, this means the victim is younger than 18 years old. If it has a flake of the bone is beginning to fuse, the age range the victim is put at is 15-21 years old. After the flake has completely fused this is categorized as between 24 and 29 years old.

Now I am sure you are thinking, what if the victim is older than 29? This is where looking at the pubis comes in handy. Below is a picture of a pelvis, the area circled in red is the area forensic anthropologists use for this method of aging. They use the area where the pubis come together, so they really just need one of the pubis. This area varies very drastically throughout the time when you age. The image below the one of the pelvis is a diagram they use when aging a pubis; the reason there are two images of each is to show how much of a variation that might occur. As you can see, on the first column, it is very bumpy and rough. But as you progress looking further to the right it begins to get smoother and more pitted; this is due to degeneration. The one with “1” under it is for the 95% age range of 15-24, while on the one with “6” the age range changes to 42-87. The reason for the huge age gap is because it gets harder to pinpoint how old the victim is.

This brings us to the sternal (area of the rib that connects to the sternum) end of the 4th rib. The reason they use the 4th rib is because that is the rib the method of looking for age using the rib was started by looking at the 4th rib. The differences they look for lie in the surface of the bone, the surface contour, rim edge, and the rim contour (image below). These, unlike the pubis, have a smaller age range of 10 years (image below).

Next week we have a forensic facial reconstruction, which is a powerful technique which can aid in establishing the identity of the deceased. With two weeks left, I am sad to see this journey come to end...but it is not done yet!
Please feel free to comment on what you thought of the blog, or other physical anthropological subjects you would like me to cover after the weeks are done.

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Ancestry is More Than Skin Deep

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