A Lecture by Prof. Sue Black

This post will give you a little update on my PhD work, but mostly I’m going to talk about a lecture that I attended yesterday presented by Professor Sue Black at the Royal Society of Medicine.

Since my last post I have been carrying out the first round of measurements and recordings to test my new method for recording dental wear. The next step to do complete some statistical analysis and to highlight and issues that need to be rectified. I think the plan is to do these tests, make some adjustments and additions to the method and then repeat the recordings. I should imagine that I will be doing this a few times to ensure a robust and accurate is produced.

To take a little break from my PhD work a couple of friends and I had a trip into London. A few weeks ago a friend of mine told me about the Royal Society of Medicine‘s Jephcott Lecture. This year’s lecture was by the esteemed Professor Sue Black, and entitled: the Real World of Forensic Anthropology

I had didn’t really have any expectations before going into the lecture, although I had heard that Sue Black was a wonderful speaker – which I can confirm! I thought that there might be a discussion of the differences between the public’s perception of forensic anthropology and the reality, and there was a bit, but the lecture was so much more than that. It started off pretty light hearted by highlighting some of the skills needed by a forensic anthropologist, e.g. the ability to distinguish between human and animal, but quickly moved onto some case examples.

The first example case was of a young man whose remains were found in some woods, it was later discovered that he had committed suicide. The following case was of a women, murdered by her husband. In both examples, Prof Black explained clearly how each case was solved, and expressed the importance of particular bits of evidence. For example, a shard of bone was discovered in the second case and instead of being destroyed, to provide DNA evidence, it was examined and identified as being part of the sphenoid bone, located within the cranial vault. This meant that the case could be increased to a murder or manslaughter charge because anyone who had that part of their skull damaged would not have survived. If the bone had been used for  DNA only it would have only revealed the individual’s identify, a fact that had already been confirmed from blood spatter. It was clear that Prof Black wanted to demonstrate the importance of forensics and the impact that it can have on a case’s direction and intent.

Following these cases the lecture focused on the forensic anthropologist’s role in the identification of sexual predators. When I first read about this lecture I had not realised that it would have taken this route, however, it was extremely interesting, although very sad. In some cases of sexual assault the abuser will take photographs that will include parts of their body, as well as the victims. Professor Black informed the audience that a recent approach in the identification of such abusers related to the pattern and visible variation in the veins, freckles, wrinkles and other physical characteristics. Over time Prof Black, and her department, have helped to compile a database to investigate this variation and have conducted research to identity whether it can prove useful in a court of law to convict an individual of a crime.

As I have said it was an extremely interesting lecture, and there was certainly food for thought afterwards! I do hope that more research and funding can go into the area of forensic anthropology.

In addition to the lecture content there were two other take home messages. The first was to not believe any of the science on CSI, or similar detective shows. It’s true that they are (extremely loosely) based on a type of forensic anthropology, but they are incredibly misleading. I have recently started watching Bones (a bit late on the band-wagaon I know!) and I must admit I do enjoy it, whilst ignoring some of the horrible inaccuracies! However, if I was a member of the public, with no or little real knowledge about forensic anthropology, I can see how damaging these shows are. They create an expectation of what could be achieved that the real world just can’t live up to. My personal recommendation would be if you enjoy watching these shows – great, but please read around the subject, read biographies of real forensic anthropologists, watch real (and creditable!) documentaries. It is a fascinating subject, but the public must be accurately informed. 

The second message that Professor Black gave was that if you want to work in the world of forensics study a hard science. Forensic anthropology is a huge field and taking a course to study the subject in general will not be enough. Study chemistry, biology, anatomy. These are just a few of the subjects that are a part of the forensic sciences. So to any aspiring forensic anthropologists – take Sue Black’s advice, she is the one to follow!

Jefferson Bass – A New Series of Books to Read

'The Bone Yard'. Image taken from here.

‘The Bone Yard’. Image taken from here.

Recently, when I went home, my Mum gave me a new book to read called ‘The Bone Yard’ by Jefferson Bass. I thought I recognised the name and quickly came across the website jeffersonbass.com and it was revealed that is a writing team consisting of Dr. Bill Bass and Jon Jefferson. Dr. Bass is a world-famous forensic anthropologist and Jon Jefferson is journalist, writer, and documentary filmmaker.

Dr. Bass is well-known for founding the research facility based at the University of Tennessee called ‘the Body Farm’. The research that is carried out investigates what happens to the human body after death and use techniques in attempt to identify time since death. Dr. Bass has authored many books and papers that provide insights into the process of decomposition. One of these include a book entitled ‘Beyond the Body Farm’ and I highly recommend it for those who would want to gain an insight into his work and research, and it’s application to real-life cases.

I was therefore very intrigued to read ‘The Bone Yard’ and I was not disappointed. I have read many of the novels by Patricia Cornwell and Kathy Reichs, both well-known forensic anthropologists and writers, so I am not new to this genre. ‘The Bone Yard’ was just as well written and informed as both Cornwell and Reich’s books but I felt there was an even better sense of realism. This novel went even deeper and further into the methods and techniques used in forensic anthropology compared to the other authors and  even provided real life examples. I recognised some of the real life situations used as I had recently read ‘Beyond the Body Farm’ and they were in there, however an author’s note at the end of the book also noted which were real and those of fiction.

I really enjoyed ‘The Bone Yard’ as I typically like this type of fiction, however, I enjoyed it even more due to the amount if detail and technical language, which was frequent but well explained. I would recommend this book to those who have an interest in forensic anthropology and have read Patricia Cornwell or Kathy Reichs, but be aware that it is a little different. It has clearly been written by authors who know their subject very well and are capable of explaining complicated methods. I am very much looking forward to getting and reading Jefferson Bass’s other fiction works, as well as Dr. Bass’s non-fiction books.

A Look at the Accuracy of Dental Age Estimation Charts

A child's skull before all of the deciduous teeth are lost.

A child’s skull before all of the deciduous teeth are lost.

So it’s now the 4th of July and I haven’t created a new skull of the month and I don’t think I will. Over the past few months I’ve been really rubbish at updating my blog and the reason behind that – I’ve been applying for jobs and working out what I’m going to do at the end of July (my current contract is ending and I have to decide whether to re-sign it or not!)

Anyway, because of all this I’ve decided that for July I’m going to try and catch-up with some of the articles that I’ve wanted to share over the past couple of months. Some relate to various skulls of the month whilst others are just articles of interest. Ideally, I’m going to do a couple a week (depending on how many applications I have outstanding!) so fingers crossed!

To start with I’m going to read an article by AlQahtani, Hector and Liversidge called ‘Accuracy of dental age estimation charts: Schour and Massler, Ubelaker and the London Atlas’. During my osteology courses at university I used both the Schour and Massler and Ubelaker for estimating age from dental remains. I came across the article a while back and I just haven’t got round to reading it. 

This particular study caught my eye because it’s aim was to compare the accuracy of estimating age from developing teeth from the above methods. When using these types of methods, using illustrations and charts to form an estimate, it is important that they are reassessed over time to test their accuracy. This is essential in subjects like archaeology and anthropology where the outcome of the result could be very fundamental.

I have discussed in the past how teeth are used for aging skeletal collections. These answers help to provide a profile of the individual and in forensic environments could potentially lead to the identification of a missing person. In archaeology age at death is used as an indicator of a populations health, providing an insight into past life and communities. In both situations obtaining an accurate and reliable age estimate is key, and therefore it is necessary that the common methods used for this process are assessed periodically.

The article by AlQahtani, Hector and Liversidge first provides a small amount of background to each of the chosen methods under study.  This image of Schour & Massler should be familiar to any osteology student. It depicts 21 drawings of dental development from the age of 31 weeks in utero up until adulthood. The method was apparently criticized in the early days due to the lack of information about the material or the method to provide the images. Since the original production in 1941 revisions have been made of  Schour & Massler’s atlas with the use of radiographs.

Schour & Massler's 1944 chart, taken from A Test of Ubelaker’s Method of Estimating Subadult Age from the Dentition (E. Smith 1999( p.30.

Schour & Massler’s 1944 chart, taken from A Test of Ubelaker’s Method of Estimating Subadult Age from the Dentition (E. Smith 1999) p.30.

In 1978 Ubelaker attempted to improve the method for obtaining age estimates from dental development and used a number of published sources. This method was seen as one which covered a the range of variation that can been seen at each stage of development. Again, most osteologists will have seen the following chart.

Ubelaker's 1989 chart, taken from A Test of Ubelaker’s Method of Estimating Subadult Age from the Dentition (E. Smith 1999) p.31.

Ubelaker’s 1989 chart, taken from A Test of Ubelaker’s Method of Estimating Subadult Age from the Dentition (E. Smith 1999) p.31.

Finally, there is the London Atlas which has combined many resources to create a dental chart that includes 31 age categories. This cart is tooth specific and defines each tooth by the development of it’s enamel, dentin, and pulp cavity.  The other bonus is that this chart has been made freely available here.

Second page of the London Atlas showing the development of individual teeth avaiable here.

Second page of the London Atlas showing the development of individual teeth available here.

That’s the method under investigation briefly covered now onto the study. As I have already mentioned the aim of the study was to assess the accuracy of estimating age from developing teeth using the three methods above. In order to do this a large sample of skeletal remains of known age at death was used. This included 183 individuals who were aged between 31 weeks in utero to 4.27 years and a further 1323 individuals (649 male and 674 female) aged between 2.07 and 23.86 years. In addition to skeletal remains the archived dental radiographs of living patients were also used. From this the age estimates were made using the three methods chosen for study and compared to the chronological age. To determine the reliability of the aging methods statistical analysis, including a paired t-test was carried out.

Before moving onto the results it is worth mentioning that intra-observer error was taken into account. This means that the same individual contacted the age estimates multiple times of a sub-set of the study sample. From doing this it was found that the error rate was low, meaning taht there was excellent when repeated for all three of the methods.

So the final results. The method which produced the closest age estimate to the chronological age was the London Atlas. For the other two methods it was found that they both under-estimated by around 0.75 years. This result was attributed to the amount of categories produced by Schour & Massler and Ublekaer as their age categories are much larger as the individual ages. This potentially misses out important development phases which can provide a more accurate age estimate. This is true of the growth of the third molar. As can be seen in the dental charts above the development of this molar is not depicted in detail, unlike the London Atlas. Due to this AlQahtani et al. removed the age estimates using the third molar and discovered that both the Schour & Massler and Ubelaker charts still under-estimate the age but only by 0.5 years. In comparison the London Atlas had a mean difference of 0 years.

This study showed, that whilst all three methods of estimating age using dental development is fairly accurate the London Atlas performed the best. As stated above these tests are important to the study of osteology and anthropology. This is because determining the age at death is vital of identifying individuals and establishing the health of a population for their dead. These studies cause researchers to constantly check their methods and to further their work in order to obtain the most reliable system that is possible, which is extremely important.

References

S. J. AlQahtani, M. P. Hector and H. M. Liversidge (2014). ‘Accuracy of dental age estimation charts: Schour and Massler, Ubelaker and the London Atlas.’ In the American Journal of Physical Anthropology Volume 154, Issue 1, pages 70–78, May 2014

E. SMith (1999). ‘A Test of Ubelaker’s Method of Estimating Subadult Age from the Dentition’. A Thesis Submitted in Partial Fulfillment of the Requirements for the Degree of Master of Science in Human Biology in the Graduate School of the University of Indianapolis May 2005.

A New Read: Bones: A Forensic Detective’s Casebook

Ubelaker bookOn the train on my way home from work I started to read a book which I got for my birthday back in October and have been meaning to read it. It’s called ‘Bones. A Forensic Detective’s Casebook’ by Dr. Douglas Ubelaker and Henry Scammell. Now to be honest I haven’t come across Henry Scammell before but I have certainly heard of Dr. Ubelaker. If you’re a biological or forensic anthropologist you will have almost definitely came across him in one way or another. Ubelaker has published books and papers on forensic and archaeology issues including estimating aging in populations. He is also a well-respected forensic anthropologist who consults on cases. Basically he is one of the big names in physical anthropology.

I have been meaning to read this book ever since I received it. I only managed the first chapter today but it’s already enthralling. I am definitely looking forward to reading about the many cases and experiences he has had. I love reading about forensic cases as my own university course was focused more towards archaeology and so I didn’t get to learn that much about the forensic side of things. Hopefully it will make my journey home go a lot quicker, and I might actually wish it to last longer at times, just so I can reach the end of a chapter!