What is an Osteobiography?

Pic: The beginning of writing an osteobiography always starts with what can be a lengthy process of note-taking.

I’ve stated the word “osteobiography” a few times in my blog posts.  Recently it occurred to me that although I know what I’m talking about, others might not!  So today I’ll give you a brief introduction to what an osteobiography is, and the process of writing one.  First things first, it takes years of training and experience to learn how to analyze skeletal remains and write up osteobiographies.  Osteoarchaeologists (bioarchaeologists interchangeably) have spent their time learning the necessary skills and knowledge, and gathering the important experience, to learn how to do this.  That’s why we’re designated as “osteoarchaeologists”.  Many archaeologists have a basic set of knowledge/recognition of human skeletal elements (we refer to individual bones as ‘elements’), but it’s always best to have an osteoarchaeologist handy to lend their specialized skills when skeletal remains are found.  Even if it’s just to identify whether an uncovered bone is human or not.  In fact, a large part of my work is doing exactly that.  So, shameless self-promotion time, hire an osteoarchaeologist if you encounter human remains or think you’ll encounter human remains (*awkwardly clears throat* I’m usually available)!

Pic: My specialized training makes it possible for me to not only recognize when something is beyond expected variation, but also to recognize possible causes for those variations. 

So, what is an osteobiography?  It’s exactly what you’re probably thinking.  An osteobiography is someone’s personal life history as told by their skeleton.  Think of a skeleton as a book written in a language osteoarchaeologists can understand (and translate).  We’re familiar with every bump, groove, hole, and rough spot there is, from the top of our heads to the tips of our toes.  Our skeletons are a blank slate that’s shaped by life experiences.  No two skeletons are alike.  The fact that we’re all different is what makes us all alike.  That being said, there is a certain level of skeletal variation we come to expect.  These expected variations help us determine things like biological sex, age, height, and levels of fitness.  So when we see bumps, grooves, holes, and rough spots out of place, or enhanced, or varied in many other ways beyond the expected level of variation, that’s something to take note about.  Those unexpected variations give us information about things like occupation (yep, even your job can alter your skeleton), disease, trauma, congenital conditions, and metabolic conditions (usually resulting from improper diets).  Sometimes we see intentional modifications, like cranial or dental modifications, which can give us ideas about levels of social inequality.  Or, in the case of medical modifications, we can get at some understanding of medical care in the past (though in some circumstances medical care can be linked to social inequality).  And finally, through testing certain stable isotopes, like 12C and 13C (carbon), δ15N (nitrogen), δ34S (sulfur), and 18O (oxygen), we can look at diet and mobility patterns.  Not only that, but because our bones are constantly remodelling themselves throughout the duration of our lives (the bones we’re born with are not the bones we die with), at varying rates depending on the size of the bone, testing the teeth and different bones will give you information related to different periods of a person’s life.  Our adult teeth develop in childhood, so testing an adult tooth will give you values from a person’s childhood.  Because ribs are so much smaller than our femurs, testing a rib will give you a more recent value (it takes less time to remodel itself) and testing a femur will give you an older value (takes longer to remodel itself).  Though it’s written about an animal skeleton and not a human skeleton, the process is the same so take a look at my recent wolverine post for an example of a complete osteobiography.

How do we write osteobiographies?  As I’ve already stated a few times now, it takes a lot of time and a lot of practice to learn how to “read” a skeleton and write out a biography.  Because of variations and the fact that our data is coming from a person who died a long time ago (excluding forensics where a person has died more recently), and because the only “normal” thing about us is that we’re all different, we don’t say anything with 100% certainty.  We say “most likely to be…”.  For example, after taking a look at all the skeletal markers that might tell me about a person’s age, I’ll say “This person was most likely between the ages of 25-45 years old” (expect large ranges when it comes to age).  When it comes to determining causes for pathological variations (disease, trauma, congenital conditions, metabolic conditions), we develop a differential diagnosis of suggestions for what might have caused those variations.  In other words, a list of possibilities.

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Pic: Some, but not all, of my reference books.

Beyond experience and knowledge, it’s SUPER IMPORTANT to have a good reference collection of books and, if possible (this depends on where you’re working/what you have access to) an actual skeletal comparative collection.  Believe it or not, like all scientists, osteoarchaeologists don’t know everything all the time.  Especially when it comes to pathologies (there are A LOT).  In addition, having a reference collection helps you be more confident and certain in your work.  So make sure you’ve got your books handy and a large work space to spread out in.  Make sure you’ve got a trusty book on adult osteology (I’m a fan of Tim White’s “Human Bone Manual”), a trusty book on juvenile osteology (I’m a fan of Schaefer et al.’s “Juvenile Osteology”, especially the slightly smaller field manual. You’re welcome for linking to a downloadable PDF), and a trusty book with information on determining age, sex, height, and what measurements to take (perhaps the most important book to have in your reference collection is Buikstra and Ubelaker’s “Standards for Data Collection from Human Skeletal Remains”).

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Pic: My travel reference collection consists of my most used/recommended books.

For starters, we lay out the skeleton on the table, whether it’s complete or not, in correct anatomical position.  Once you’re ready, with a notebook handy for taking notes, you work your way through each bone or fragment, recording everything you see (and sometimes feel).  I personally prefer to record it all by hand in a notebook, but many others use printed work sheets to record their observations.  This also varies according to how much time you have available (less time = better to use worksheets).  Standards (1994) has all the worksheets you need.  So, regardless of written notes or worksheets, spend time going through every bone/fragment you’ve got.  Your sense of touch is incredibly important.  Sometimes something looks normal, until you pick it up and feel it.  Sometimes the weight is off.  Sometimes it’s a little rougher than usual.  Sometimes it’s too thick or too thin.  It’s better to write too many notes than too few.  Be patient because it can take hours to get through a single skeleton (but this includes the time it takes to set it up and put it away).  Once you’ve finished taking your notes (or I prefer to do it as I’m going along so it’s fresh in my mind), take photos!  Lots of photos, from lots of angles.  It’s good to have a photo of the whole skeleton/all the fragments, but even more important are photos of specific variations you’ve made note of.  Photos will always supplement notes, and notes will always supplement photos.  And when you’re taking notes, make sure you have a photo scale in the picture!  I have definitely been guilty of forgetting to include a photo scale and it makes my life a little more difficult later.

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Pic: examples of worksheets from Standards (1994)

Once you’ve got all your notes and photos taken, it’s time to start interpreting.  What are those notes telling you?  That large bump in that odd spot on the left humerus – what could that mean?  The right clavicle looked a little “swollen” – what could have caused that?  This is where books and journal articles really come in handy.  Go through any book or article you think might be of use.  Does that strange bump look like trauma?  Go through books and articles on trauma.  Does it look like disease?  Go through books and articles on disease.  Find anything that’s comparable enough for you to say, “I think this might be it.”  Be prepared for never having a specific answer.  Many times we simply have to say, “I don’t know”, despite our thorough notes and observations.  Most of the time, as I’ve already mentioned, you’ll have a list of a bunch of possibilities.  And that’s totally fine.  In fact, it’s encouraged.  Sometimes we can use aDNA to help guide our conclusions, but aDNA can be finicky or, depending on the disease you’re looking to identify (I’m pointing at you, sphyilis), aDNA might be of no use at all.  Sometimes you might have enough information to say “infectious disease” or “trauma”, but not enough to give you more specific causes.  Again, it’s totally fine not to have all the answers.  Osteobiographies have a level of uncertainty built into them.  Of equal importance is being prepared to be wrong.  If something is difficult to ID, as I’ve already talked about, chances are you’re going to be wrong every once in a while.  Leave yourself open to challenges and alternative interpretations from colleagues in the field.  It will only help you in the long run.

So there you have it. At the end of the several days (or longer) it can take to build a single osteobiography, you’ve got a picture of what someone’s life was like as told to you through their skeleton.  You could know how tall they were, places they lived, and foods they ate.  You might also know about injuries they suffered or infections they had.  Maybe even what kind of physical labour they were engaged with on a regular basis.  Osteobiographies are very, very personal.  You might know something about someone they didn’t know themselves.  Or perhaps they never told anyone else.  If the skeleton is from an archaeological site, keep in mind that person didn’t ask to be on your table being studied.  ALWAYS treat them with the utmost respect and if you’re working with the descendant community, listen to and respect the wishes of their descendants.

Tl;dr Summary

Writing an osteobiography is a lengthy process which requires a lot of skill, knowledge, and patience.  It’s always best to hire someone with the experience to do it, or at the very least, train you how to do it.

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