Does the skeletal structure of humans interest you? Are you a sucker for a good murder mystery novel? Do you find yourself watching TV shows that analyze forensics? Then this might just be for you!
Today, us field schoolers dove into the world of forensic anthropology (which may also be referred to as bioarchaeology or biological anthropology) with a lecture and workshop run by Dr Trudi Buck. One of the coolest parts about this workshop was when we were given two sets of partial skeletons (plastic cast versions based off of genuine skeletal remains) and were given the tools and knowledge required to make some scientific observations. While I’m sure you’ve read about this lecture in previous years, I thought I would change it up and share some of the specific skills I learned today.
The mixture of (plastic) bones spread out across the table before being sorted and organized.
We were able to work in small groups with this activity, which allowed us to really get hands-on. Aline and I worked together to separate the two skeletons based on size. We were told in advance that some of the bones belonged to an adult and others belonged to a child.
A view of the spine from the child’s skeleton.
Once we differentiated the child-size bones from the adult-sized bones, our next step was to organize the bones from the adult’s skeleton to recreate the natural skeletal structure. My background knowledge on biological anthropology is minimal, so I found that this was one of the harder parts of the day but it was a fun challenge. It was especially interesting to see where the bones meet up with each other and how they function based on the shapes at joints.
Avery comparing the interior structure of a human hand to its outward appearance.
The Age of the Deceased
The lecture taught us how to determine an age range based on certain characteristics of the bones, and how certain aspects change over time. For instance, when trying to put an age range on the skeletal remains of a child, the teeth and jaw are the most accurate method to determine this. When trying to determine the age range of a skeleton that has already undergone puberty, things such as bone fusion and the general ‘wear and tear’ of bones can be used.
Avery examining the fully fused coccyx bone from the skeleton of an adult.
The sex of the Deceased
In biological anthropology there are various methods that have been used to determine whether a skeleton belongs to a male or female, but the most effective method examines the pelvis. Based on the overall shape of the bones, biological anthropologists can determine sex. Although this is the most reliable way, it is not the only one.
When the pelvic bone is not present, the structure of the skull can be looked at, with general differences between the sexes. If DNA is available from the remains, scientific testing can determine the sex.
A chart and image depicting the general differences between male and female skulls, with the male skull on the top and the female skull on the bottom.
Other variations between the sexes can be used in situations where neither the skull nor the pelvis has been found, but these rely on general traits and can vary depending on geographical location.
The Origin of the Deceased
Now for those who have followed the blog and are familiar with what I have already written, you’ll know that I am not very science-oriented. But to tell the origin of a human from their remains, scientists do an isotope analysis from the enamel on the teeth. Basically, depending on where someone grows up, the water they drink and the general oxygen levels in their teeth can differ. The oxygen levels can be determined through the isotope analysis, which will provide a general geographical range of where someone grew up.
Dr. Buck explaining the oxygen levels in isotopes.
Theory versus Practice
In a perfect world, when archaeologists stumble upon human remains, they would be complete skeletons accompanied by some sort of inscription to tell the name, sex, origin, and age of the person to leave out any need for guessing. Short of that, a full skeleton without an inscription would still be ideal. This way the bones might be able to tell a full story and provide at least as close as possible ranges for this information. But often this is far from the truth. Sometimes there are a handful of bones that include the jaw and pelvic bone to give the important information biological anthropologists are looking for. Other times there is only a skull to work from. And even when bones are found, depending on the ancestry of the individual, statistics and averages may point to one sex while DNA points to another. Sometimes there is no DNA to test. But it seems to me that three things that are very important in the field of biological anthropology are background knowledge, practice, and a hands-on approach. Thanks to Dr. Buck, we got a taste of what goes into this field of study, and what we can tell from human remains.
This activity involved a bit of speculation, a fair amount of hard work, and ended up being a lot of fun!
The plastic skull.
Bye for now,