A Day of Statistics, Isotopes and Drilling Bones

I’m Richard Madgwick,  a zooarchaeologist employed as a British Academy post-doctoral fellow at Cardiff University. So what’s my day of archaeology been like? Having just left Çatalhöyük on Wednesday after nearly three weeks in Anatolia, I’m very much playing catch up on research that has had to take a back seat since I’ve been away. I’ve spent much of the day feeling envious of the remaining Çatalhöyük faunal team who are all enjoying a trip to Göbekli Tepe today – I picked the worst time to leave!!

Me staring a bone out

Me staring a bone out

My day has been split between two research projects – one tedious (but worthy!) and the other more practical and interesting. I spent the morning doing some multivariate statistical analysis on a large dataset of around 25,000 animal bones. I’m using a snappily named approach called backwards stepwise binary logistic regression to assess what factors impact on the preservation and modification of animal bones in the archaeological record. This follows on from my PhD research and I’m currently looking in to the causes of abrasion of archaeological bones. Trampling, exposure to acidic conditions, utilisation, earthworm activity. bioturbation, boiling and roasting and water action have all been cited as causes of abraded (or polished) bone but until we know the factors that are important in its occurrence it’s difficult to make any sense of patterns.I spent the afternoon drilling, abrading, weighing and demineralising bone samples from the late Neolithic site of Durrington Walls, next to Stonehenge. I now have 50 chunks of pig jaw happily fizzing away in weak acid in the lab. This is the first part of the sample preparation for isotope analysis – in this instance I’ll be analysing the samples for carbon, nitrogen and sulphur isotopes. Later I will also be testing the teeth from the jaws for strontium isotopes. This aim of the game is to understand more about how pigs were raised and where they came from. Durrington Walls is a huge feasting site and we know some cattle at the site came from Scotland thanks to the work of Sarah Viner and Jane Evans. It’s much more difficult to drag a pig over such distances, but I’m hoping I can get some evidence for long distance movement – pigs were of great importance to the feasts here and I think there’s a good chance they were sourced from a wide area. This will provide us with evidence of where people came from to take part in these great feasts.

Amy Thorp: Roman Pottery Specialist

While I spend many of my days as a pottery specialist handling lots of pretty objects, today is a statistics day. Quantification is a vital tool for inter-site comparison so lots of time is spent trawling through our databases. At the moment I’m looking at a City site near the location of the Roman forum with an assemblage totalling a mere 24,000 sherds. I’m also returning to DUA reports (Department of Urban Archaeology for those who remember) for comparative data from a nearby site.

Amazing how quickly reports date – look at that font!


Alaskan Archaeological Adventures in Digital Terrain Analysis

Sarah here. I am just getting this post in right at the last minute (so mind my grammar) but I thought I’d contribute and support this day because Jess is one of my dearest friends and I couldn’t have survived my M.Sc. in Archaeological Computing at Southampton without her! Anyway I will stop being gushy and tell you a bit about what I have been working on up here in ALASKA!

A client of ours last year asked for an “archaeological probability model” to assess the potential for discovering cultural resources within a proposed 2000 foot wide by 116 mile road through the Northern Brooks Range and North Slope of Alaska (way above the Arctic Circle). I will not go into the debates about predictive modeling in this blog but as you may know these models have definite pros and cons. This model was to accompany approximately 65 days of archaeological survey field work in the summer of 2010 (we are just now getting funding to continue this summer). This road is being proposed through a remote area where the Alaska Natives still rely heavily on caribou and seasonal fishing trips (for those of you who are familiar with Lewis Binford’s work, god rest his soul, he studied the Nunamiut or Inland Eskimo quite intensively and this project is within their traditional territory). The road is being designed to open up oil and gas fields (sigh).

So I decided to get in contact with a college of mine in Alberta, Canada who is well versed in archaeological predictive/potential modeling. He has been using available high resolution DEMs (digital terrain models) produced by Light Detecting and Ranging (LiDAR) elevation data to perform digital terrain analysis and multi-criteria analysis to construct archaeological potential (suitability) models. So I decided to give it a shot seeing as we had a LiDAR DEM!
To accomplish this task, I utilized terrain analysis (LandSerf©) to highlight two types of landforms with a higher potential for the presence of archaeological sites. These two landforms are level areas near terrain breaks (such as terrace breaks-in-slope), and ridges. I selected these landforms because they are consistent with observations concerning site location made by archaeologists in northern Alaska. I then ranked the archaeological potential of these landforms based on proximity to higher order streams (fish bearing rivers are the highest) using a multi-criteria analysis (IDRISI©).
So now I am working on a field survey plan to test the model this summer. I am not nearly done and there is a chance the helicopter is going to be ready to take us out there next week! Oh boy, I’d better get after it!

Data analysis in the afternoon

Some people say the morning is the best time to write, but I like the afternoon.  In the morning I’m too distracted by all the various to-dos that I know are on my list for the day; I find I’m better off getting some of those things done in the morning and then plopping down in front of the computer after lunch. The only problem with this schedule is that it seems many others use afternoons as their errand time.  So while my phone, email, etc tend to be blissfully silent in the morning, in the afternoon, if I need to leave my phone/email on for some reason (or if I just forget to turn them off) it’s a constant stream of interruptions.  So it has been this afternoon.


My plan for the afternoon had originally been to finish up an article on one part of the Navajo project – it’s almost there.  But then I got several emails/phone calls, all about different important matters that don’t take much time to address but which I did need to deal with.  Unfortunately, I don’t deal with distractions at all well while writing; I really need a block of time in which to concentrate.  So I abandoned ship on finishing the article today.  Maybe over the weekend.


Instead, I turned to data and statistics.  The beauty of this kind of work in this situation is that it’s something I can do with interruptions – in fact, I find interruptions to be useful.  I can keep thinking about a data problem in the back of my head while dealing with something else.


So today when interruptions derailed my writing, I turned to my Spanish project.  Earlier this summer, I was in Valencia, Spain, looking at a zooarchaeological collection of leporids (or rabbits) from the site of Cueva de Nerja.  Now, it’s time to take those data and figure out what they mean.  My question in looking at these rabbit bones has to do with how the rabbits were being hunted.  Did the prehistoric inhabitants of Nerja take these on the landscape?  Or did they hunt them using a mass capture technology, such as netting?  The way to answer this question is by looking at the demography of the rabbits in question – are there lots of young rabbits, or mostly older ones?  More males or females?  Are there changing patterns through time, and if so, are those patterns statistically significant?