July 31, 2014

Open Osteological Data - Two Imperial Roman Cemetery Populations

I defended my dissertation, Migration and Mobility in Imperial Rome, four years ago.  Because of my interest in open access and because my NSF grant required a data access statement, I've been thinking for four years about how best to open up all the data I collected.

At first, I was worried about opening up the data because I wanted to get a job.

I got a job in 2012 at the University of West Florida.  

Roman Osteology Database Screenshot
Then I worried about opening up the data because I needed to publish and get tenure, but growing interest in open data among scholars made me conflicted.  So I compromised: I posted all published isotope data as bare-bones Excel files.  But divorcing these data from their larger context didn't sit well with me.

I'm entering my third year at UWF, and I see no reason to hold back the database any longer.  While I'm still a ways from making my tenure case, I've been steadily publishing the plethora of data I generated during my dissertation fieldwork, so I feel confident in my ability to research, analyze, and write on bioarchaeology.  

More importantly, though, I think I'm just done with this project.  

That's not to say there isn't more to write or that there aren't more data to analyze or that I'm not still interested in this time and place.  There's a ton of dental and skeletal pathology data, for example, that I haven't tackled.  But I want to move on to other projects, and at this point I worry that I'm becoming too myopic.  Honestly, Imperial Rome tends to do that -- it sucks you in, making you think it is, was, and ever will be the most important city in the world full of the most important people in history.  Roman imperialism is calling out for more diverse perspectives, though.  The rise in osteological analysis of Romano-British cemeteries, for example, is created a multifaceted Empire.  And new multidisciplinary studies in the Transatlantic slave trade are raising the question of potential comparative work with slavery in the Roman world.  I still love answering questions about population interaction in the past, but I might try focusing that interest on times and places like Medieval Berlin, Greco-Roman Italy, or Pre-Emancipation Southeast U.S.  Still, I am working on skeletons from various time periods at Gabii, so I haven't abandoned Roman bioarchaeology.  And I might yet publish dental pathology data (or enlist a grad student to do it for a thesis)...

At any rate, you can find my Access database on GitHub at this link.  Please use it if you're interested in comparative data sets, if you want to check my work, if you disagree with my interpretations, or if you just like reading databases.  I only ask that you credit me appropriately.  (If you want to collaborate further for a publication, though, I'm happy to do that as well.)

What follows is the repository read-me for more info. Some pictures are posted; more to come as I find the time to wade through and post them. Note that the database is partly embargoed; I feel bad about this, but for various reasons (that I'm happy to explain over a beer, but not here) I will make all the data available within the next year when publications are submitted and/or come out.  Also note that no archaeological context information is available for these two cemetery populations; I didn't dig up these skeletons, so I have only included data that I personally generated.  Someday, I hope to find an alternative to this Access database that I wrote in 2007 (maybe ARK? maybe an app I design?), but I'm not a fan of Osteoware or other non-open methods of recording skeletal data.  A blank version of my database is also available on GitHub.

I hope this database is useful.  While I realize I'm not being fully open with all my data just yet, I hope that this can set a precedent for other bioarchaeologists.  There's nothing more I'd like to see than large-scale, world-wide comparisons of health, diet, disease, and migration in antiquity.

Roman Osteology [Read-Me] - https://github.com/killgrove/RomanOsteology

This repository contains my database of published and unpublished data resulting from my research on skeletal remains from two cemeteries in Rome, Italy (Casal Bertone and Castellaccio Europarco). There are also photographs relevant to various publications, each labeled by skeleton number (which is the ID key in the Access database).

In the database, you will find basic demographic information (age and sex), an inventory of each skeleton, skeletal pathology data, records of teeth examined and their pathological conditions, and results of all biochemical analyses undertaken to date (C, N, O, Sr, Pb isotopes; Pb and Sr concentration). Note that adult measurements, subadult measurements, subadult dental data, and nonmetric cranial trait data will be available in the next year, once the relevant publications come out (I'm afraid I have to embargo these raw data for the moment). Data from my work at Casal Bertone and Castellaccio Europarco can be found here; data from Gabii will be posted when possible. No information on the archaeological context of the skeletons (e.g., provenience, grave goods, etc.) is included in this database, as that information is the purview of the Archaeological Superintendency of Rome. Download the database by clicking on the "Download" button (over there on the lower right toolbar) and open with Microsoft Access.

The photographs folder currently includes shots of all individuals with scoreable porotic hyperostosis. Photographs are also available for many of the individuals with enamel hypoplasia, but photographs were not taken of every individual or every tooth with this enamel insult. More photographs will be posted soon, largely related to various pathological conditions (osteoarthritis and fractures among them).

I'm suggesting a CC BY-NC-SA license for these -- that is, feel free to use the data as you see fit for your academic publications; I just ask that you credit me appropriately. To find my own analyses and interpretations, or to get additional context, please see the relevant publications. If you don't have access to them, I will gladly send you a copy of anything published or under review:

[Pathology Data]
  • Killgrove, K. Submitted (July 2014). Imperialism and physiological stress in Rome (1st-3rd centuries AD). Manuscript submitted for edited volume, Bioarchaeology of Contact, Colonialism, and Imperialism, H. Klaus and M. Murphy, eds. University Press of Florida.
[Sr and O Data]
[C and N Data]
[Pb Data]
[Nonmetric Trait Data]
  • Killgrove, K. Submitted (December 2012). Using biological distance techniques to investigate the heterogeneous population of Imperial Rome. Manuscript submitted for edited volume, The Archaeology of Circulation, Exchange, and Human Migration, D. Peterson and J. Dudgeon, eds.

July 22, 2014

How long was the average Roman foot, and what was their shoe size?

Archaeologist Eric Poehler just keeps coming with the questions about Roman walking and feet.  Today, he wanted to know the size of the Roman foot.  In my last post, I'd kind of given up on the idea of figuring out foot size, since I didn't think I had any foot measurements.  Then I remembered this morning that of course I have calcaneus maximum length.  The trick was to find a formula using calcaneus maximum length to approximate foot size.

Sandaled foot from the Augustan period (Met Museum)
This was more difficult than you'd think.  There are a metric TON of articles that relate shoe/foot size to stature, but you have to have the shoe/foot (these are useful in forensic contexts, of course).  So I could use long bones to calculate stature and then use stature to calculate approximate foot size, but that would introduce one more level of error than I need.  It seems like no bioarchaeologists care about estimating foot size from foot bones, which surprised me because I'd assumed at least comparative primate morphologists would be interested in this.  (Now, of course, there is growing interest in Roman walking because of databases like Stanford's ORBIS.)

I did find what I was looking for, though, in literature related to lower leg changes in polio: Anderson, M., M. Blais, and W.T. Green. 1956. Growth of the normal foot during childhood and adolescence. Length of the foot and interrelations of foot, stature, and lower extremity as seen in serial records of children between 1-18 years of age. American Journal of Physical Anthropology 14(2):287-308.  This article is helpfully available for free via PDF here.  If you scroll through to page 306, there's a handy chart that gives you the percentage of the foot made up by the "calcified os calcis" (what we now simply call the calcaneus).  Taking 18-year-olds (as the authors have concluded that the foot is no longer growing at this point), we find that the calcaneus makes up 30.2% (+\- .1) of the male foot and 28.9% (+\- .1) of the female foot.  Spiffy!

Now, we take the maximum calcaneus lengths from the population I studied at the Imperial-era Casal Bertone cemetery, 2km east of Rome. The male average was 80mm (8 cm), and the female average was 75mm (7.5 cm).  Using the power of multiplication, the average Roman male foot was 26.5cm, and the average Roman female foot was 25.9cm.  If you want to go a step further (ha!), this means the average Roman male from Casal Bertone wore a US 8.5 / EU 42 shoe, and the average female a US 10 / EU 41 shoe.  Boom -- calculating calcanei!

The female numbers seem too long, honestly, but I can believe the male numbers.  If you recall my previous post, the average male stature from this site was about 167cm, and female stature was 157cm.  So (using Imperial measurements now, sorry, but I'm American!) a 5'6" man could easily wear an 8.5 US shoe.  But a 5'2" woman would not wear a 10 US shoe.  I'm 5'9" and I wear a 10.

If there really aren't equations other than this to approximate foot size from calcaneal length, I suddenly have an MA project in mind for an interested student... And the correlations between bone length and shoes (as from Vindolanda) have lots of potential as well!

July 18, 2014

How long was the average Roman stride?

Eric Poehler (@Pompeiana79) posed this question on Twitter this morning. Katy Meyers (@BonesDoNotLie) and Keith Chan (@ChekeiChan) commented that there are formulae to estimate stride based on height. The forensic articles I found were actually going in the reverse -- from footfalls/strides to height (which makes sense if you want to find a murder, for example).  Keith suggested exercise medicine articles, and the most often-quoted article, Hatano, Y. "Use of the pedometer for promoting daily walking exercise." International Council for Health, Physical Education, and Recreation 29.4 (1993): 4-8., suggests two factors for calculating average step length: .415 for males and .413 for females (times height in centimeters).  Note that this is step length not stride; in exercise research, step length is the distance from, say, the left heel to the right heel (or left toe to right toe), whereas stride is the distance between the heel of the left foot to the heel of the left foot (two steps).

So using stature data from my dissertation, I calculated that the average Imperial Roman male (from Casal Bertone, 2km east of the walls of Rome) who stood 166.6cm would have a step length of 69.1cm, which means a stride length of roughly 140cm. Females in the population stood on average 156.7cm, so that's 64.7cm step length and 130cm stride length. There is plenty more stature data in my diss if y'all want to do more calculations, of course!

If I were to go full-on XKCD What If?, I'd look not only into the differences in stature among the Roman population (again, see my dissertation), but also into foot size from both foot bones and from the ginormous shoe cache at Vindolanda to refine the estimate. But I didn't measure any Roman foot bones at any of the sites I've worked at, and most of this research and writing was done on my phone during the 20 minutes my 9-month-old napped on me this morning.  Checking the Vindolanda research and looking into Troy Case's work with the bones of the feet are good avenues to go in.

And, of course, as the Rogue Classicist (@RogueClassicist) points out, all of this is largely theoretical anyway because people would have been wearing different things.  That is, the stride factors above are probably for modern Americans in comfy workout clothes, not for Imperial Romans wearing stiff togas or heavy armor.

But this is just another example of the fun of Twitter.  Just like with my "Where did Roman babies poop?" question a few weeks ago, we collectively had a random research question asked and partly answered, with lots of follow-up and collaborative potential!

July 15, 2014

Presenting Anthropology - New Links to Others' Cool Stuff

Ever since I taught Presenting Anthropology, a graduate proseminar, in the spring of 2013, I've been thinking about new and different ways to do public outreach and have been saving links to clever projects by others.  Here are a few links I came across this morning and had to share:

  • Drunk Archaeology -- Two students in my Presenting Anthropology course (Zach and Andy) created a Drunk Archaeology video on analogy with Drunk History, starring fellow grad student Will.  Because they are all students and want jobs someday, they did not feel comfortable having the video on the very public internet, which is understandable.  Fast-forward to this month, and archaeologist Andrew Reinhard has created a tumblr/podcast/Twitter/etc. called Drunk Archaeology.  He plans to interview archaeologists while drunk (duh) and is also interested in archaeology-themed drink recipes (which Presenting Anthro student Becca did for one of her projects).  Do check out Drunk Archaeology to see what Andrew and others get up to.  I think this outreach effort will mostly reach other archaeologists, but since the Drunk History videos have such wide appeal, perhaps the general public will be interested as well.
  • An Evolution-Themed Nursery Rhyme -- This is a really clever idea that I'd never thought of, in spite of having two little girls myself.  NPR's Tania Lombrozo enlisted some help to put together a short-but-sweet nursery rhyme/song about the natural selection of cute violet spiders.  I can't wait for my 5-year-old to get home from school so I can show it to her:

  • And finally, Let's Mummify Barbie.  My 5-year-old thinks that everyone who dies turns into a mummy (which I confirmed by mentioning her recently-deceased great-grandfathers, whom she says are mummies now) because we haven't ever gone to a funeral but have been to a variety of museums and have seen a lot of mummies.  If your kid wants to mummify his or her doll, there are instructions at the link for that.

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